I do not understand this and could use help it needs the work shown

9514 1404 393

Answer:

  (x, y) = (3, 12)

Step-by-step explanation:

The first step in any problem solving is to look at the problem. Here, we see that the first equation can be reduced to standard form by dividing it by 2. This would give both terms a coefficient of 1.

We see that the second equation already has a variable with a coefficient of 1.

When solving a system by substitution, it can save some effort if you start by finding a variable with a coefficient of 1 or -1. Since we see that in the second equation, we choose to solve the second equation for y:

  y = 4x . . . . . . . add 4x to both sides of the second equation

Now, we have an expression for y that we can substitute into the first equation.

  2x +2(4x) = 30 . . . . substitute for y

  10x = 30 . . . . . . . . simplify

  x = 3 . . . . . . . . . . divde by 10

  y = 4(3) = 12 . . . . . find y using y=4x

The solution is (x, y) = (3, 12).

__

Additional comment

I doesn't matter what variable gets substituted. The purpose of the exercise is to reduce the number of variables in the equation. Here, we start with an equation that has 2 variables. Substituting for one of them gives an equation with only one variable, a lot easier to solve.

You don't have to find an expression for the "bare" variable. We could solve the second equation for 2x, for example: 2x = y/2, then substitute for 2x in the first equation: y/2 +2y = 30   ⇒   y = (2/5)(30) = 12. Or, we could solve the first equation for 2x and substitute into the second: 2x=30-2y, y-2(2x) = 0 ⇒ y-2(30-2y) = 0 ⇒ y = 60/5 = 12.

The substitution property of equality says you can make any substitution of equal values anywhere. "butter = margarine" means you can substitute butter for margarine, or vice versa, wherever you may wish.

[tex]\\ \large\sf\longmapsto x + 15 = 2x - 40 \\ \\ \large\sf\longmapsto x - 2x = - 40 - 15 \\ \\ \large\sf\longmapsto - x = - 55\\ \large\sf\longmapsto x = 55[/tex]

The value of x is 55 degrees.

A rhombus is a diamond-shaped quadrilateral that has all four sides equal

The properties of a rhombus are:

According to the given question.

We have a rhombus.

Since, we know that the diagonals of the rhombus bisect the angles.

Therefore,

[tex](x+15)^{o} = (2x-40)^{o}[/tex]

Solve, the above expression for x.

[tex]\implies x +15 = 2x -40\\\implies 15+40 = 2x -x \\\implies 55 = x \\0r\ x = 55^{o}[/tex]

Hence, the value of x is 55 degrees.

Find out more information about rhombus here:

https://brainly.com/question/12189679

#SPJ2

Answer:

C- 35 °

Step-by-step explanation:

Interior angle adjacent to 90° angle = 90° (supplementary angles of a line segment).

Interior angle adjacent to 125° angle = 55° (supplementary angles of a line segment).

Sum of two interior angles of the triangle = 55+90 = 145°

∠p = 180° - 145° = 35°

Answer:

at 15.39% that should not be sufficient to reject the Null

= "Fail to reject the Null hypothesis"

Step-by-step explanation:

z = -1.02 (L)0.15386 (R)0.84614

84.61% / 15.39%

Answer:

Since we know the dot product of unit vectors, we can simplify the dot product formula to a⋅b=a1b1+a2b2+a3b3. we can use the same formula, but with a3=b3=0, a⋅b=a1b1+a2b2.

Step-by-step explanation:

Answer: the answer is 3

Step-by-step explanation:

I just took the test

Answer:

The mean is the average number of a data set gotten by adding all the numbers then dividing by two.

the median is the middle number in a sorted set of data,either sorted in ascending order or descending order.

I hope this helps

To calculate mean:

• add up all the numbers,

• then divide by how many numbers there are.

Example:

Data: 5, 6, 10, 1

Add these all together, which is 22, then divide by 4 (because that is how many numbers there are), so:

the mean is 5.5

To calculate median:

Arrange your numbers in order.

Cross off numbers until you get to the middle.

If there is an even number of data, then find the two in the middle and find the middle of that.

Example:

Data: 5, 6, 10, 1

Arrange: 1, 5, 6, 10

So, the middle 2 are 5 and 6. In between these would be 5.5, so that is the median.

If the data was: 1, 5, 6, 8, 10,

then the median would be 6.

Answer:

A. Increase the level of confidence

Step-by-step explanation:

The margin of error is given by:

The margin of error is:

[tex]M = \frac{Ts}{\sqrt{n}}[/tex]

In which T is related to the level of confidence(the higher the level of confidence, the higher T is), s is the standard deviation of the sample and n is the size of the sample.

Increase the width:

That is, increasing the margin of error, as the width is twice the margin of error, the possible options are:

Increase T -> increase confidence level.

Increase s -> Increase the standard deviation of the sample.

Decrease n -> Decrease the sample size.

Thus, the correct answer is given by option A.

Answer:

cannot understand the language man

but please follow

Answer:

Click the graph in Quadrant 1

Step-by-step explanation:

This graph is bigger in side length.

Answer:

is y=x^2 a proportional relationship?

[tex]{ \sf{yes. \: constant \: of \: proportionality = 1}}[/tex]

is y=2+x a proportional relationship?

[tex]{ \sf{no. \: unless \: y \: is \: proportinal \: to \: (2 + x)}}[/tex]

is y=2/x a proportional relationship?

[tex]{ \sf{yes. \: where \: proportianality \: constant \: is \: 2}}[/tex]

is y=2x a proportional relationship?

[tex]{ \sf{yeah. \: constant \: is \: 2}}[/tex]

Answer:

Step-by-step explanation:

x3−x2+5x−12

x

≥0

Let's find the critical points of the inequality.

x3−x2+5x−12

x

=0

x3−x2+5x−12=0(Multiply both sides by x)

(Use cubic formula)

x=1.836169

Check possible critical points.

x=1.836169(Works in original equation)

Critical points:

x=1.836169(Makes both sides equal)

x=0(Makes left denominator equal to 0)

Check intervals in between critical points. (Test values in the intervals to see if they work.)

x<0(Works in original inequality)

0<x≤1.836169(Doesn't work in original inequality)

x≥1.836169(Works in original inequality)

Answer:

x<0 or x≥1.836169

Step-by-step explanation:

Let the husband's income be x

Wife's income be x + 9000

X + X + 9000 = 81000

2X + 9000 – 9000 = 81000 – 9000

2X= 72000

X = 36000

Husband, 36000,

Wife, 9000+36000, 45000

Answer <1 = 145

< 2= 35

<3 = 35

Step-by-step explanation:

<1 + <4 = 180 (supplementary since you can find corresponding side and straight angle)

<1 = 180-35

=145 degrees

<2 =<4 corresponding angles

<2 = 35 degrees

<3 = 35 degree (corresponding to <2)

Answer:

B. 24.

Step-by-step explanation:

3

4 = 2*2

6 = 2*3

8 = 2*2*2

LCM = 2*2*2*3 = 24

Answer:

27

Step-by-step explanation:

Let T be the capacity of the tank.

Since the tank was 1/3 full and ends up 7/9 full.

         [tex]\frac{7}{9}[/tex]T - [tex]\frac{1}{3}[/tex]T = 12  

Simplifying the left side of the equation, tells us how much 12 gallons fills.

         [tex]\frac{4}{9}[/tex]T = 12

Now we solve for T:

         T = 12*9/4

         T = 27

Answer:

Here we only need to analyze the vertical motion of the ball.

First, because the ball is in the air, the only force acting on the ball will be the gravitational force (we are ignoring air resistance), then the acceleration of the ball is equal to the gravitational acceleration, so we have:

a(t) = -32 ft/s^2

where the negative sign is because this acceleration is downwards.

To get the velocity equation, we need to integrate over the time, so we get:

v(t) = (-32 ft/s^2)*t + V0

where V0 is the initial velocity of the ball. In this case, the initial velocity of the ball will be the velocity that the ball had when it was dropped, which should be the same as the velocity of the hot air ballon, so we have:

V0 = 12 ft/s

Then the velocity equation of the ball is:

v(t) = (-32 ft/s^2)*t + 12 ft/s

To get the position equation we integrate again:

p(t) = (1/2)*(-32 ft/s^2)*t^2 + (12 ft/s)*t + H0

Where H0 is the initial height. We know that the ball was released at the height of 1120 ft, then we have:

H0 = 1120 ft.

Then the position equation is:

p(t) = (-16 ft/s^2)*t^2 + (12 ft/s)*t + 1120ft

a)  How many seconds after its release will the ball strike the ground?

The ball will strike the ground when its position equation is equal to zero, then we need to solve:

p(t) = 0 ft = (-16 ft/s^2)*t^2 + (12 ft/s)*t + 1120ft

This is just a quadratic equation, the solutions are given by Bhaskara's formula, so the solutions for t are:

[tex]t = \frac{- 12ft/s \pm \sqrt{(12 ft/s)^2 - 4*(-16ft/s^2)*(1120 ft)} }{2*(-16ft/s^2)}[/tex]

We can simplify that to get:

[tex]t = \frac{-12ft/s \pm 268ft/s}{-32ft/s^2}[/tex]

So we have two solutions:

[tex]t = \frac{-12ft/s + 268ft/s}{-32ft/s^2} = -8s[/tex]

[tex]t = \frac{-12ft/s - 268ft/s}{-32ft/s^2} = 8.75s[/tex]

The negative solution does not make sense, then the correct solution is the positive one.

We can conclude that the ball will hit the ground after 8.75 seconds.

b)  At what velocity will it hit the ground?

We already know that the ball strikes the ground 8.75 seconds after it is released.

The velocity at it hits the ground is given by the velocity equation evaluated in that time:

v(8.75 s) = (-32 ft/s^2)*8.75s + 12 ft/s = -268 ft/s

Answer:

5180.56 Dollars...........

Answer:

- 27.88

Step-by-step explanation:

Probability of earthquake = 0.0012

P(earthquake). = 0.0012

P(no earthquake) = 1 - p(earthquake) = 1 - 0.0012 = 0.9988

X ____ 60,000 ______ - 100

P(X) ___ 0.0012 _____ 0.9988

The expected value of the policy :

E(X) = Σx*p(x)

E(X) = (0.0012 * 60000) + (0.9988 * - 100)

E(X) = 72 - 99.88

E(X) = - 27.88

Answer:

12

Step-by-step explanation:

πr²h=πr²h

π(4.5)²*10=π(x/2)²4.9

Answer:

u = 18

Step-by-step explanation:

The two angles 3u and u+36 are equal so

3u = u+36

Subtract u from each side

3u -u = u+36-u

2u = 38

Divide by 2

2u/2 = 36/2

u = 18

C-x=-5

Step-by-step explanation:

-3x=-15

or,-3x x =-15

or, x=-15÷3

therefore, x=-5

Answer:

A) 128

B) 7800

Step-by-step explanation:

Trial and error until I got to 75 x 104 and 60 x 128 (which abides by the fact that there has to be 24 more red boxes) which equals 7800 and 7680 and if you take them away from each other you get 120

Answer:

m∠F = 45°

Step-by-step explanation:

Notice the lengths of the given sides and the right angle. This is enough information to prove that this is a 45-45-90 triangle, or just basically a square cut diagonally.

Regardless if even just one side is given for a 45-45-90 triangle, all 45-45-90 triangles have one thing in common. The sides that form the right angle are equivalent and the hypotenuse is equal to one of the sides that form the right angle times the square root of two. I'm aware that it sounded confusing, as I'm awful at explaining, so just look at the picture I've attached instead of trying to understand my explanation that seemed like trying to learn a second language.

Look at the picture. See that FD = x times that square root of 2 and that DE = x. Now look back at your picture. It's connecting, now isn't it?

Now that we know that this is indeed a 45-45-90 triangle, we can confirm that m∠F = 45°

Answer:

75 inches

Step-by-step explanation:

with this we use change of subject

V=1/3

Pie=3.14

radius =3

height =8

so therefore

V=1/3 ×3.14×3×3×8

V=75.36

Answer:

5а⁶=а⁶+а⁶+а⁶+а⁶+а⁶

~~~~~~~~

Answer:

Bayes’ Theorem describes the probability of occurrence of an event related to any condition. It is also considered for the case of conditional probability.

For prove refer to the attachment.

Hope this helps you^_^

After storing 5/9 in the large silo there was 4/9 left ( 1-5/9 = 4/9)

A. Multiply 4/9 by 3/4:

4/9 x 3/4 = 12/36 = 1/3

1/3 of the corn was in the small silo.

B. 1-5/9 -1/3 = 4/9-1/3 = 4/9-3/9 = 1/9

1/9 of the corn went to market:

18 x 1/9 = 18/9 = 2

2 ton went to market.

y = 2/3 x - 2

Or

y + 2 = 2/3 ( x )

Answer:

y= 2/3x - 2

hope this helps :)