A circle centered at $P$ with radius $10$ and a circle centered at $Q$ with radius $8$ are externally tangent. A common external tangent intersects line $PQ$ at $R.$ Find $QR.$

The region inside cardioid r = 1 + cos(θ) and outside the circle r = 3 cos(θ) is equal to [tex]\frac{\pi}{4}[/tex]

Now, According to the question:

We will first draw both of them on the same plane and then find their point of intersection. Then using the given information, we will shade the region whose area we have to find.

The point of intersection of  r = 1 + cos(θ) and  r = 3 cos(θ)

1 + cos(θ)  = 3 cos(θ)

1 = 2 cos(θ)

=> cos(θ) = 1/2

=> θ = [tex]cos^-^1[/tex][tex]\frac{1}{2}[/tex]

=> θ = ±[tex]\frac{\pi }{3}[/tex]

So, two curves intersect at θ = ± [tex]\frac{\pi }{3}[/tex]

Area of the cardioid,

[tex]A_1 = \int\limits^\pi _\frac{\pi }{3} {\frac{1}{2}(1+cos\theta)^2 } \, d\theta= \frac{1}{2} \int\limits^\pi _\frac{\pi }{3} (1+cos^2\theta+2cos\theta) } \, d\theta=\frac{1}{2}[/tex]

          [tex]\int\limits^\pi _\frac{\pi }{3} {(1 + \frac{cos2\theta+1}{2} +2cos\theta)} \, d\theta[/tex]

 => [tex]A_1 = \frac{1}{2}[\theta+\frac{1}{2}(\frac{sin2\theta}{2} +\theta)+2sin\theta ]^\pi _\frac{\pi }{3}[/tex]

=> [tex]A_1= \frac{1}{2}[\frac{3\pi }{2}+0+0-\frac{\pi }{2}-\frac{\sqrt{3} }{8} -\sqrt{3} ][/tex]

=> [tex]A_1= \frac{1}{2} [\pi +\frac{-9\sqrt{3} }{8} ]\\\\A_1 = \frac{\pi }{2} - \frac{9\sqrt{3} }{16}[/tex]

Area of the circle,

[tex]A_2 = \int\limits^\frac{\pi }{2} _\frac{\pi }{3} {\frac{1}{2}(3cos\theta)^2 } \, d\theta \\\\A_2 = \frac{9}{2} \int\limits^\frac{\pi }{2} _\frac{\pi }{3} \frac{cos2\theta+1}{2}d\theta\\ \\A_2 = \frac{9}{4}[\frac{sin2\theta}{2}+\theta ]^\frac{\pi }{2}_\frac{\pi }{3}[/tex]

[tex]A_2 = \frac{9}{4}[0+\frac{\pi }{2} -\frac{\sqrt{3} }{4} -\frac{\pi }{3} ][/tex]

[tex]A_2=\frac{9}{4}[\frac{\pi}{6}-\frac{\sqrt{3} }{4} ][/tex]

[tex]A_2= \frac{3\pi }{8}-\frac{9\sqrt{3} }{16}[/tex]

Area of the shaded region,

[tex]A = A_1-A_2[/tex]

[tex]A = \frac{\pi }{2} - \frac{9\sqrt{3} }{16} - \frac{3\pi }{8}+\frac{9\sqrt{3} }{16}[/tex]

[tex]A = \frac{\pi }{8}[/tex]

This is the area of the shaded region in the first and the second quadrant. We see that by symmetry, the area of the shaded region in the first and the second quadrant is equal to the area of the shaded region in the third and the fourth quadrant.

So, the total area is 2 ×[tex]\frac{\pi}{8}[/tex] = [tex]\frac{\pi}{4}[/tex]

Hence, the region inside cardioid r = 1 + cos(θ) and outside the circle r = 3 cos(θ) is equal to [tex]\frac{\pi}{4}[/tex]

Learn more about Area of the circle at:

https://brainly.com/question/28642423

#SPJ4

The probability of picking a solid color on the 4th day is 8/10 = 4/5.

The probability of picking a solid color on the 4th day is calculated by taking the total number of solid color pairs remaining in the drawer and dividing by the total number of pairs remaining.

On the first three days, you picked 1 black pair and 2 blue pairs, so you have 3 black pairs, 3 blue pairs, 3 brown pairs and 2 multi-colored pairs left in your drawer.

The total number of solid color pairs remaining is 8, and the total number of pairs remaining is 8+2 = 10.

So, the probability of picking a solid color on the 4th day is 8/10 = 4/5.

Learn more about conditional probability and counting here: https://brainly.com/question/10567654

#SPJ4

Answer: x = 81

Step-by-step explanation:

Quite a straightforward question.

Given equation is 61+20=x

So you just need to add 61 and 20 to get the value of x,

x=81

Therefore , the solution of the given problem of interest rate comes out to be $271.94 you will be depositing every month.

The original capital is multiplied by the interest rate, the loan term, and other factors to calculate simple interest. A simple return is equal to the principal plus interest hrs. This method of calculating interest is the simplest. The most typical method is to calculate it as a fraction of the principal amount. For instance, he was only liable for paying his portion of the interest if he acquired $100 from a buddy and agreed to repay the money on 5% interest. $x (0.05) = $5. When you make loans or lend money, you both have to pay interest. Interest is frequently determined as a percentage of a loan.

Here,

Given  :  interest = 9%

time  =35 years

amount = 800000

Using formula :

=> FV.( r / [tex](1+r) ^{n}[/tex] -1)

=>  800000 (0.09/12 / [tex](1 + 0.09/12 )^{12*35}[/tex] - 1 )

=> 271.94

Therefore,

the total amount you deposit will only be

=> 35*12 times $271.94, or

roughly total amount => 35*12*271.94= 114214.8 dollars, out of the estimated $800,000.

The balance will be what the account earns or accumulates over the next 35 years.

Therefore , the solution of the given problem of interest rate comes out to be $271.94 you will be depositing every month.

To know more about interest visit:

https://brainly.com/question/28792777

#SPJ1

The simplification of rational expressions can be achieved by using the Greatest Common Factor (GCF).

Take the common terms in the numerator and denominator and remove them from the expression to make it simpler.

The simplification of rational expressions can be achieved by using the Greatest Common Factor (GCF).Similar to fractions with variables in the denominators, rational expressions appear like them (and often numerators too).

For instance, the expression x 2 x + 3 is a rational expression: x squared, divided by x, plus 3, end fraction.

1)2m^2-4m)/2(m-2)

=[2m(m-2m)]/2(m-2)

= 2m/2

=m

2)m^2-2m+1/m-1

= (m-1)^2/(m-1)

=(m-1)(m-1)/(m-1)

=(m-1)

3)m^2-3m+2/m^2-m

=m^2-m-2m+2/m(m-1)

=m(m-1)-2(m-1)/m(m-1)

= (m-1)(m-2)/m(m-1)

=(m-2)/m

To learn more about rational expression refer

https://brainly.com/question/10242441

#SPJ1

The prime factorization of the radicand 2 is 9√15.

A number can be expressed as the product of its prime components through the process of prime factorization. A number with precisely two elements, 1 and the number itself, is said to be a prime number.

As an illustration, let's use the number 30. We know that 30 = 5 × 6, but 6 is not a prime number. The number 6 can further be factorized as 2 × 3, where 2 and 3 are prime numbers. Therefore, the prime factorization of 30 = 2 × 3 × 5, where all the factors are prime numbers.

Given that,

x= 3√135

Solving the equation further using the rule √A*B = √A*√B

x= 3√9*15

x= 3√9*√15

x=3*3*√15

x= 9√15

Therefore, the prime factorization of the radicand 2 is 9√15.

To know more about prime factorization visit: brainly.com/question/29775157

#SPJ4

Therefore , the solution of the given problem of equation comes out to be x² + z²= y, a circular paraboloid.

When a math formula employs the equals symbol (=), it appears to be a rule that connects two expression and denotes equality. An equation in algebra is a factual declaration that shows that several mathematical variables are all equal. For instance, the values ptdc + 6 and 12 in the equation obd + 6 = 12 have an equal sign. The link between the words on either side of each letter is described by a mathematical formula. The sentence and the insignia are frequently same.

Here,

The vector solution is r(s, t) = s, t, t² - s².

When comparing to r(s, t) = x, y, and z, x = s, y = t, and z = 2 - s²

So, z = y² - x²

, a hyperbolic paraboloid (2)

r(s, t) = s sin³t, s², s cos³t is the vector equation that is presented.

When comparing with withr(s, t) = x, y, and z,

x = ssin³t, y = s², and z = s* cos³t²

As a result, x2 + z2 = s2 (sin23t + cos23t),

sin23t + cos23t = 1,

x² + z² = s², s² = y, and x² + z²= y,

a circular paraboloid.

Therefore , the solution of the given problem of equation comes out to be x² + z²= y, a circular paraboloid.

To know more about equation visit:

https://brainly.com/question/649785

#SPJ4

The correct equations to represent Ted's total September costs are: (3600+ 1.50) x 12.000 1.50(3600+) 12,000.

Cost is the total expenditure or loss incurred in the production, acquisition, or use of a product or service. It can be calculated as the sum of fixed costs (such as rent and labor costs) plus variable costs (such as materials and energy). Cost can be expressed both in monetary terms (such as dollars or euros) or in terms of resources (such as time or effort). In business, cost is a crucial factor for determining profitability and should be taken into consideration when making decisions about production, sales, and pricing strategies.
The first equation calculates the cost of the fixed monthly costs plus the cost of the 16 ounce bags of coffee multiplied by the total number of bags sold. The second equation calculates the cost of the 16 ounce bags of coffee multiplied by the fixed monthly costs plus the total number of bags sold.

To know more about cost click-
https://brainly.com/question/25109150
#SPJ4

Answer:

D

Step-by-step explanation:

There are no black shoelaces

Answer:

B.

Step-by-step explanation:

You need to find a common denominator.  In this case, 40.  Convert 2/5 to 16/40 and 3/8 to 15/40.  Add the numerators (16 + 15) together.  The denominator stays the same.

$2094.28 interest will she pay by the time the loan is repaid.

What is compounded monthly?

Theoretically, continuously compounded interest means that an account balance continuously earns interest as well as reinvesting that interest into the balance so that it too earns interest.

As we know the formula of per month installments

[tex]E.M.I = \frac{P*r*(1+r)^n}{(1+r)^n^-^1}[/tex]

By putting the value of P (loan applied for)=$5500

r (Monthly rate of interest)  [tex]= \frac{6.8}{12*100}[/tex]

n = number of monthly installments = 10 × 12 = 120

[tex]E.M.I = \frac{5500*(\frac{6.8}{12*100} )(1+\frac{6.8}{1200} )^1^2^0}{(1+\frac{6.8}{1200} )^1^2^0-1}\\ E.M.I= \frac{5500*0.00567*1.971}{1.971-1}\\ E.M.I = \frac{61.461}{0.971} \\E.M.I = 63.29[/tex]

E.M.I.=$63.29

Total Installments of loan =120

Therefore total amount paid against loan = $63.39 × 120 = 7594.28

So interest paid = 7594.28 - 5500= $2094.28

Hence, $2094.28 interest will she pay by the time the loan is repaid.

To know more about compounded monthly, click on the link

https://brainly.com/question/1397205

#SPJ4

Answer:

Step-by-step explanation:

The height of her pear tree is 20 inches

First subtract 46 from 26 to get 20. So 20+26=46inches

x=20

Step-by-step explanation:

you know how to transform an equation ?

you need to apply the same operating to both sides of the equation. always. otherwise the equality relation is destroyed.

x + 26 = 46

to get to "x = ..." the "+ 26" is in the way.

clearly we need to subtract 26. but we need to do it on both sides.

x + 26 - 26 = 46 - 26

x = 20

that simply means the last tree is 20 in.

it is 26 in shorter than 46 in (fig tree).

that's all there is to it.

The probability of being born on a Tuesday is= 18/343

The area of mathematics known as probability deals with numerical representations of the likelihood that an event will occur or that a statement is true.

An event's probability is a number between 0 and 1, where, roughly speaking, 0 denotes the event's impossibility and 1 denotes certainty.

The likelihood that an event will occur increases with its probability.

A straightforward illustration is tossing a fair (impartial) coin.

The coin is fair, thus the outcomes "heads" and "tails" are equally likely; the likelihood of "heads" is equal to the likelihood of "tails"; and because there are no other conceivable outcomes, the likelihood of either "heads" or "tails" is 1/2 (which is also an acceptable spelling).

Hence, The probability of being born on a Tuesday is= 18/343.

learn more about probability click here:

brainly.com/question/13604758

#SPJ4

Answer:

240 seats with tables

Step-by-step explanation:

Let's start by making our fraction out of 10 on the first train to make it easier on us, this fraction would be [tex]\frac{6}{10}[/tex]. Then, to get the number of seats on this train that would have a table, we need to multiply 400 by our fraction, giving us:

[tex]400 * \frac{6}{10} = 2400/10 = 240[/tex]

So, the 1st train should have approximately 240 seats with tables.

Hope this helped!

According to Westgard and CLIA , 40-100  specimens should be run by each method on the same day for 8 to 20 days to compare a test method with a comparative method.

CLIA stands for  Clinical Laboratory Improvement Amendments  . The regulations under CLIA includes, the federal standards which is applicable to all U.S. facilities or sites which are test human specimens for health assessment or it is used to diagnose, prevent, or treat disease.

The Federal Register is the official daily publication for federal agencies and the organization's notices, proposed regulations, and final rules, as well as executive orders and other presidential papers. The regulations published in the Code of Federal Regulations and enforced by federal agencies are known as final rules.

To learn more about CLIA

brainly.com/question/29342147

#SPJ4

If in parallelogram ABCD, AB = 14cm. The altitude corresponding to AB is 6 cm and the altitude corresponding to BC is 7 cm. The AD is 8.57.

Given data:

AB= 14cm

Altitude corresponding  AB =6cm

Altitude corresponding to BC =7cm

So,

1/2 × AB × altitude 1 = 1/2 × AD × altitude 2

AB × altitude 1 =AD × Altitude 2

10 × 6 = AD × 7

60 = AD × 7

AD = 60/7

AD = 8.57

Therefore we can conclude that AD is 8.57.

Learn more about altitude here:https://brainly.com/question/1159693

#SPJ1

According to the given information the area of the parallelogram is 300ft².

A geometric shape having parallel sides in two dimensions is called a parallelogram. It is a type of four-sided polygon where each parallel set of sides is the same length (commonly referred to as a quadrilateral). The adjacent angles of such a parallelogram add up approximately 180 degrees.

Width of parallelogram = 20 feet.

Base of triangle = 4 feet.

Height of triangle = 15 feet.

To figure out the parallelogram's surface area:

To begin with, we would calculate the triangles' surface areas.

Note: The parallelogram supplied can be divided into two (2) triangles.

the triangle's surface area formula.

The formula: yields the triangle's area mathematically.

[tex]\begin{matrix}\mathrm{\ Area\ }=\frac{1}{2}\times\mathrm{\ base\ } \times\mathrm{\ height\ } \\\mathrm{\ Area\ }=\frac{1}{2}\times4\times15\\\mathrm{\ Area\ }=2\times15\\\mathrm{\ Area\ }=\mathbf{30}f^2\\\end{matrix}[/tex]

For the two (2) triangles:

[tex]Area =2\times30\\Area =\mathbf{60}ft^2[/tex]

For the rectangle left:

[tex]Length =15ft.\\Width =20-4=16ft.\\Area = length \times width\\Area =15\times16\\Area =\mathbf{240}ft^2[/tex]

Now, the area of the parallelogram:

Area of parallelogram =60+240

Area of parallelogram [tex]=\mathbf{300}{\rm ft}^2[/tex]

To know more about parallelogram visit:

https://brainly.com/question/15052855

#SPJ4

The minimum number of poles to be Erected for fencing are 26.

The perimeter of a rectangle is -

P = 2{L + B}

Given is that a rectangular field measures 63.9 meters by 104.6 meters.

The perimeter of the rectangular field will be -

P = 2(63.9 + 104.6)

P = 2(168.5)

P = 337

Let the total number of poles that can be erected are {x}. Then, we can write that -

2.4x ≤ 63.9

x ≤ (63.9/2.4)

x ≤ 26.66

x = 26 {approx.}

Therefore, the minimum number of poles to be Erected for fencing are 26.

To solve more questions on rectangles, visit the link below -

brainly.com/question/12802031

#SPJ1

On solving the provided question we can say that 50 vehicles, 11 of which are damaged, leave 39 intact. Conditions for inference are satisfied because both proportion number of successes and failures is greater than 10.

Relationships that consistently have the same ratio are referred to as proportionate. For instance, the average quantity of apples per tree determines how many trees there are in an orchard and how many apples are in a harvest of apples. In mathematics, proportional denotes a linear relationship between two numbers or variables. The other amount doubles when the first quantity does. The other lowers as well when one of the variables falls to 1/100th of its prior value.

Yes, the prerequisites for inference are satisfied.

Inference requirements:

The sample must have at least 10 successes and 10 failures in order to construct a confidence interval for a population proportion.

50 vehicles, 11 of which are damaged, leave 39 intact.

Conditions for inference are satisfied because both the number of successes and failures is greater than 10.

To know more about proportionality visit:

https://brainly.com/question/29126727

#SPJ4

If g(x) is the inverse function of f(x)  and[tex]$f^{\prime}(x)=\frac{1}{1+x^4}$[/tex], then [tex]$g^{\prime}(x)$[/tex]  is [tex]1+[\mathrm{g}(\mathrm{x})]^4\end{aligned}[/tex]

Correct option is A)

[tex]& \mathrm{g}=\mathrm{f}^{-1} \\[/tex]

[tex]& \mathrm{f}(\mathrm{g}(\mathrm{x}))=\mathrm{x}[/tex]

Differentiate w.r.t.x

[tex]& \mathrm{f}^{\prime}(\mathrm{g}(\mathrm{x})) \cdot \mathrm{g}^{\prime}(\mathrm{x})=1 \\[/tex]

[tex]& \therefore \frac{1}{1+(\mathrm{g}(\mathrm{x}))^4} \cdot \mathrm{g}^{\prime}(\mathrm{x})=1 \\[/tex]

[tex]& \mathrm{~g}^{\prime}(\mathrm{x})=1+[\mathrm{g}(\mathrm{x})]^4\end{aligned}[/tex]

The complete question is,

If [tex]$\mathrm{g}(\mathrm{x})$[/tex]is the inverse function of [tex]$\mathrm{f}(\mathrm{x})$[/tex] and [tex]$\mathrm{f}^{\prime}(\mathrm{x})=\frac{1}{1+\mathrm{x}^4}$[/tex], then [tex]$\mathrm{g}^{\prime}(\mathrm{x})$[/tex]is

A [tex]$1+[\mathrm{g}(\mathrm{x})]^4$[/tex]

B [tex]$1-[g(x)]^4$[/tex]

C [tex]$1+[\mathrm{f}(\mathrm{x})]^4$[/tex]

D [tex]$\frac{1}{1+[\mathrm{g}(\mathrm{x})]^4}$[/tex]

To learn more about Inverse function refer to:

https://brainly.com/question/3831584

#SPJ1

Answer:

0.9583

Step-by-step explanation:

(2-1) * (23÷24)

1*0.983

=0.9583

Answer:

[tex]\frac{23}{24} = 0.95[/tex]

Step-by-step explanation:

According to BODMAS

The height of the prism is 5x + 3 units.

What is volume?

A measurement of three-dimensional space is volume. It is frequently expressed numerically using SI-derived units, as well as different imperial or US-standard units. Volume and the definition of length are related.

Given:

The volume of a rectangular prism is given by the expression

10x^3 + 46x^2 – 21x – 27. The area of the base of the prism is given by the expression 2x^2 + 8x – 9.

We have to find the height of prism.

Volume of the rectangular prism = Base × Height

The expression is in the Question be

10x ³ + 46 x² - 21x -27

And the  area of the base of the prism is given by the expression

2x² + 8x - 9 .

Put in the formula

10x ³ + 46 x² - 21x -27  = 2x² + 8x - 9  × Height

The factor of 10x ³ + 46 x² - 21x -27 are (5x +3 )(2x² + 8x - 9) .

put in the formula

(5x +3 )(2x² + 8x - 9) = (2x² + 8x - 9) × Height

Cancelled 2x² + 8x - 9 on both side.

(5x+3)unit = Height

Hence, the height of the prism is 5x + 3 units.

To know more about volume, click on the link

https://brainly.com/question/2887044

#SPJ1

After 4 years of recycling and re-using, approximately average one-half of the original 350,000 cans produced by the soft drink company would still be in use.

1. 350,000 cans produced in 1 year

2. 50% of cans recycled each year

3. 50% of 350,000 cans = 175,000 cans

4. After 4 years, 175,000 cans still in use.

Each year, it is predicted that about half of all aluminum cans will be recycled. This means that if a soft drink company produces 350,000 cans one year, then after four years, approximately one-half of the original cans produced would still be in use. This can be calculated by taking the initial number of cans produced (350,000), multiplying it by fifty percent (50%), and then multiplying that number by four (4). The final result is that after four years of recycling and re-using, approximately 175,000 cans would still be in use.

Learn more about average here

https://brainly.com/question/24057012

#SPJ4

Answer:

see explanation

Step-by-step explanation:

there isa common difference between consecutive terms, that is

[tex]\frac{a_{2} }{a_{1} }[/tex] = [tex]\frac{-3}{-2}[/tex] = [tex]\frac{3}{2}[/tex]

[tex]\frac{a_{3} }{a_{2} }[/tex] = [tex]\frac{-4\frac{1}{2} }{-3}[/tex] = [tex]\frac{3}{2}[/tex]

this indicates the sequence is geometric with nth term

[tex]a_{n}[/tex] = a₁ [tex](r)^{n-1}[/tex]

where a₁ is the first term and r the common ratio

here a₁ = - 2 and r = [tex]\frac{3}{2}[/tex] , then

[tex]a_{n}[/tex] = - 2 [tex](\frac{3}{2}) ^{n-1}[/tex] , thus

a₅ = - 2 ([tex](\frac{3}{2}) ^{4}[/tex] = - 2 × [tex]\frac{81}{16}[/tex] = - [tex]\frac{81}{8}[/tex]

and

a₇ = - 2 [tex](\frac{3}{2}) ^{6}[/tex] = - 2 × [tex]\frac{72 9}{64}[/tex] = - [tex]\frac{729}{32}[/tex]

Answer:

23.35 cubic feet

Step-by-step explanation:

The volume of a cylinder can be calculated using the formula: V = π * r^2 * h, where r is the radius of the circular base, h is the height of the cylinder.

To find the radius, we use the formula for the circumference of a circle: C = 2πr

The circumference of the circular base is 2.6 feet, so we can set this equal to 2πr and solve for r: 2.6 = 2πr, r = (2.6) / (2π) = 0.816

Now that we know the radius, we can substitute it into the volume formula: V = π * (0.816)^2 * 4.4 = 23.35 cubic feet

So the answer is 23.35 cubic feet, which closest to A. 23.35 cubic feet

Answer: 5.2 cm

Step-by-step explanation:

4.8 squared + 2 squared is 23.04 + 4, which is 27.04. The square root of that is 5.2

If y equals 7 when x equal 2/3, so when x =7/3 the y is equal to 14/7

If y varies inversely with x, this means that the product of x and y is a constant. So if we know that y = 7 when x = 2/3, then we can set up the equation: x*y = k, where k is the constant.

Substituting the known values we get: (2/3)*7 = k.

So we know that k = 14/3

Now, we can use this value of k to find the value of y when x = 7/3.

x*y = k

(7/3)*y = 14/3

y = 14/7

So, when x = 7/3, y = 14/7

To learn more about the product, visit:

brainly.com/question/3211849

#SPJ4

The values of the expression are given by the inequality below:

11/3 < 5/x + 2 < 9/2

Here we want to find the possible values of the expression:

5/x + 2

Where we have the restriction:

2 < x < 3

Notice that x is on the denominator, so when x takes the largest value x = 3, we will have a lower bound for the expression:

5/3 + 2 = 5/3 + 6/3 = 11/3

When x takes the smallest value, we will get the upper bound:

5/2 + 2 = 5/2 + 4/2 = 9/2

Then the possible values of the expression are:

11/3 < 5/x + 2 < 9/2

Learn more about inequalities:

https://brainly.com/question/24372553

#SPJ1

Answer:

First account: $16,000

Second account: $4,000

Step-by-step explanation:

Let x be the amount Christine invested in the 8% account and y be the amount she invested in the 10% account. We know from the problem that:

x + y = $20,000 (the total amount she had to invest)

0.08x + 0.1y = $1920 (the total amount of interest she received)

We can use the first equation to solve for one variable in terms of the other.

x = $20,000 - y

Now we substitute this expression into the second equation:

0.08($20,000 - y) + 0.1y = $1920

Solving for y:

0.08x + 0.1y = $1920

0.08($20,000 - y) + 0.1y = $1920

1,600 - 0.08y + 0.1y = $1920

-0.08y = -320

y = $4,000

Now, we know that Christine invested $4,000 in the 10% account, we can use the first equation again to find out how much she invested in the 8% account:

x + y = $20,000

x + $4,000 = $20,000

x = $16,000

So Christine invested $16,000 in the 8% account and $4,000 in the 10% account

Answer:

I don't know the answer to this question