Dado P(x) = x2– kx + 2, hallar el valor de k para que P( – 2)=8

Answer:

[tex]y = 2x^2 + 1[/tex]

Step-by-step explanation:

The graph you see there is called a parabola. The general equation for the graph is as below

[tex]y = a*x^2 + b[/tex]

To find the equation we need to find the constants a and b. The constant b is just how much we're lifting the parabola by. Notice it's lifted by 1 on the y axis.

To find a it's a little more tricky. Let's use the graph to find a value for a by plugging in values we know. We know that b is 1 from the previous step, and we know that when x=1, y=3. Let's use that!

[tex]3 = a * (1)^2 + 1\\2 = a[/tex]

Awesome, we've found both values. And we can write the result.

[tex]y = 2x^2 + 1[/tex]

I'll include a plotted graph with our equation just so you can verify it is indeed the same.

Answer:

x = 20

y = 70

Step-by-step explanation:

Since B and D are parallel :

6x - 10 + 3x + 10 = 180 add/subtract like terms

9x = 180 divide both sides by 9

x = 20

angle represented by y and 6x - 10 are supplementary and their sum is 180

y + 6x - 10 = 180 replace x with 20

y + 6*20 - 10 = 180

y + 120 - 10 = 180

y + 110 = 180 subtract 110 from both sides

y = 70

Answer:

3

Step-by-step explanation:

5 1/3 ÷ 1 7/9

Change to improper fractions

5 1/3 = (3*5+1)/3 = 16/3

1 7/9 = (9*1+7)/9 = 16/9

16/3 ÷ 16/9

Copy dot flip

16/3 * 9/16

Rewriting

16/16 * 9/3

1*3

3

Answer:

m∠TRS = 6°

m∠U = 103°

Step-by-step explanation:

In the given figure,

O is the center

RS ∥ VU

m∠V = 103° &

m∠VRT = 71°

So,

m∠V +  m∠R = 180°                (∵ sum of co-interior angles)

⇒  m∠R = 180° - 103°              (m∠V = 103° is given)

∵ m∠R = 77°    ...(i)

Now,

m∠R =  m∠TRS +  m∠VRT

by putting the values given

⇒  m∠TRS = 77° - 71°

∵ m∠TRS = 6°  

As we know that,

VURT is a cyclic quadrilateral. So,

m∠U +  m∠R = 180°

⇒ m∠U +  77° = 180°            (from equation (i)

∵ m∠U = 180° - 77° = 103°

The complete table of the function is:

[tex]\begin{array}{cccccccc}x & {0} & {1} & {2} & {3} & {4}& {5} & {6} \ \\ f(x) & {72} & {60} & {48} & {36} & {24}& {12} & {0} \ \end{array}[/tex]

The equation missing from the question is:

[tex]y = 72 - 12x[/tex]

To complete the table, we simply calculate the y value for each x value;

When [tex]x = 0[/tex],     [tex]y = 72 - 12 * 0 = 72[/tex]

When [tex]x = 1[/tex],     [tex]y = 72 - 12 * 1 = 60[/tex]

When [tex]x = 2[/tex],     [tex]y = 72 - 12 * 2 = 48[/tex]

When [tex]x = 3[/tex],     [tex]y = 72 - 12 * 3 = 36[/tex]

When [tex]x = 4[/tex],     [tex]y = 72 - 12 * 4 = 24[/tex]

When [tex]x = 5[/tex],     [tex]y = 72 - 12 * 5 = 12[/tex]

When [tex]x = 6[/tex],     [tex]y = 72 - 12 * 6 = 0[/tex]

So, the complete table is:

[tex]\begin{array}{cccccccc}x & {0} & {1} & {2} & {3} & {4}& {5} & {6} \ \\ f(x) & {72} & {60} & {48} & {36} & {24}& {12} & {0} \ \end{array}[/tex]

To create a graph of f(x), we simply type [tex]y = 72 - 12x[/tex] on a drawing tool and the graph will be generated.

See attachment for graph

Learn more about graphs at:

https://brainly.com/question/20106471

Answer:

Step-by-step explanation:

The final step. You divided wrong.

8 = 400 / 120  = 10/3

Step-by-step explanation:

The final step. You divided wrong.

[tex] s = \frac{400}{120} = \frac{10}{3} [/tex]

The two congruent base angles tell us that this triangle is isosceles, meaning it has two congruent sides. Therefore, we can set the two expressions equal to each other and solve from there.

9x - 73 = 3x + 23

6x - 73 = 23

6x = 96

x = 16

Side = 3(16) + 23 = 48 + 23 = 71

Hope this helps!

Answer:

x = 16

Step-by-step explanation:

Since the base angles are the same, the side lengths are the same

9x- 73 = 3x+23

Subtract 3x from each side

9x - 3x- 73 = 3x+23 -3x

6x- 73 = 23

Add 73 to each side

6x - 73 +73 = 23+73

6x = 96

Divide by 6

6x/6 = 96/6

x =16

Answer:

B. 0.024

The p-value of the test is 0.024 < 0.05(standard significance level), which means that there is enough evidence that the proportion of freshmen who graduated in the bottom third of their high school class in 2001 has been reduced.

Step-by-step explanation:

Before testing the hypothesis, we need to understand the central limit theorem and subtraction of normal variables.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]

Subtraction between normal variables:

When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.

1999:

Of 100, 20 were in the bottom thid. So

[tex]p_B = \frac{20}{100} = 0.2[/tex]

[tex]s_B = \sqrt{\frac{0.2*0.8}{100}} = 0.04[/tex]

2001:

Of 100, 10 were in the bottom third, so:

[tex]p_A = \frac{10}{100} = 0.1[/tex]

[tex]s_A = \sqrt{\frac{0.1*0.9}{100}} = 0.03[/tex]

To determine this, you test the hypotheses H0 : p1 = p2 , Ha : p1 > p2.

Can also be rewritten as:

[tex]H_0: p_B - p_A = 0[/tex]

[tex]H_1: p_B - p_A > 0[/tex]

The test statistic is:

[tex]z = \frac{X - \mu}{s}[/tex]

In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, and s is the standard error.

0 is tested at the null hypothesis:

This means that [tex]\mu = 0[/tex]

From the sample:

[tex]X = p_B - p_A = 0.2 - 0.1 = 0.1[/tex]

[tex]s_A = \sqrt{s_A^2+s_B^2} = \sqrt{0.03^2+0.04^2} = 0.05[/tex]

Value of the test statistic:

[tex]z = \frac{X - \mu}{s}[/tex]

[tex]z = \frac{0.1 - 0}{0.05}[/tex]

[tex]z = 2[/tex]

P-value of the test and decision:

The p-value of the test is the probability of finding a difference of proportions of at least 0.1, which is 1 subtracted by the p-value of z = 2.

Looking at the z-table, z = 2 has a p-value of 0.976.

1 - 0.976 = 0.024, so the p-value is given by option B.

The p-value of the test is 0.024 < 0.05(standard significance level), which means that there is enough evidence that the proportion of freshmen who graduated in the bottom third of their high school class in 2001 has been reduced.

Answer:  A. 300 m

Work Shown:

L/100 = 15/5

5L = 100*15

5L = 1500

L = 1500/5

L = 300

Answer:

8.6023

Step-by-step explanation:

length = √[(x2-x1)^2+(y2-y1)^2]

=√[(1-6)^2+(-1--8)^2] =√74 =8.6023

Answer:

Step-by-step explanation:

[tex]\tt{ \green{P} \orange{s} \red{y} \blue{x} \pink{c} \purple{h} \green{i} e}[/tex]

Answer:

D

Step-by-step explanation:

(the line is a / shape, so the slope is positive)

(the line crosses the y axis at (0,-2)

(using the above information, the equation is y=2x-2)

Answer:

y = 2x - 2

Step-by-step explanation:

Start with

y = mx + b

The graph shows the y-intercept -2.

We have y = mx - 2

slope = m = rise/run

The slope is rise of 2 and run of 1, so m = 2.

y = 2x - 2

Answer:

Bruce's tiles covered more area than Felicia's, so this means Bruce has the greater unit rate.

Step-by-step explanation:

Got it right

Answer:

Please check out the attachments below to get the answer

Answer:

The orginal number is 26.

Step-by-step explanation:

So the units digit can be 3 6 or 9

The tens digit can be 1 2 or 3

So the original number can be 13

31 = 2*13+ (1+3) + 2

31 =? 26 + 4 + 2    

This doesn't work. The right side is 32

26

62 = 2*26 + 8 + 2

62 = 52 + 8 + 2

This is your answer.

3 and 9 won't work because 39 is odd and so is 93. The result has to be even.

Step-by-step explanation:

5.

[tex](5 + 4 \sqrt{7} ){x}^{2} + (4 - 2 \sqrt{7} ) x- 1 = 0[/tex]

Simplify both radicals.

[tex](5 + \sqrt{112) {x}^{2} } + (4 - \sqrt{28} )x - 1 = 0[/tex]

Apply Quadratic Formula

First. find the discramnint.

[tex](4 - \sqrt{28} ) {}^{2} - 4(5 + \sqrt{112} )( - 1) = 64[/tex]

Now find the divisor 2a.

[tex]2(5 + \sqrt{112} ) = 10 + 8 \sqrt{7} [/tex]

Then,take the square root of the discrimant.

[tex] \sqrt{64} = 8[/tex]

Finally, add -b.

[tex] - (4 + 2 \sqrt{7} )[/tex]

So our possible root is

[tex] - (4 + 2 \sqrt{7} ) + \frac{8}{10 + 8 \sqrt{7} } [/tex]

Which simplified gives us

[tex] \frac{ 4 + 2 \sqrt{7} }{10 + 8 \sqrt{7} } [/tex]

Rationalize the denominator.

[tex] \frac{4 + 2 \sqrt{7} }{10 + 8 \sqrt{7} } \times \frac{10 - 8 \sqrt{7} }{10 - 8 \sqrt{7} } = \frac{ - 72 - 12 \sqrt{7} }{ - 348} [/tex]

Which simplified gives us

[tex] \frac{6 + \sqrt{7} }{29} [/tex].

6. The answer is 2.

9514 1404 393

Answer:

  5. x = (6 +√7)/29; a=6, b=1, c=29

  6. x = 2

Step-by-step explanation:

The quadratic formula can be used, where a=(5+4√7), b=(4-2√7), c=-1.

  [tex]x=\dfrac{-b+\sqrt{b^2-4ac}}{2a}=\dfrac{-(4-2\sqrt{7})+\sqrt{(4-2\sqrt{7})^2-4(5+4\sqrt{7}})(-1)}{2(5+4\sqrt{7})}\\\\=\dfrac{-4+2\sqrt{7}+\sqrt{16-16\sqrt{7}+28+20+16\sqrt{7}}}{10+8\sqrt{7}}=\dfrac{4+2\sqrt{7}}{2(5+4\sqrt{7})}\\\\=\dfrac{(2+\sqrt{7})(5-4\sqrt{7})}{(5+4\sqrt{7})(5-4\sqrt{7})}=\dfrac{10-3\sqrt{7}-28}{25-112}=\boxed{\dfrac{6+\sqrt{7}}{29}}[/tex]

__

Use the substitution z=3^x to put the equation in the form ...

  z² -3z -54 = 0

  (z -9)(z +6) = 0 . . . . . factor

  z = 9 or -6 . . . . . . . . value of z that make the factors zero

Only the positive solution is useful, since 3^x cannot be negative.

  z = 9 = 3^2 = 3^x . . . . use the value of z to find x

  x = 2

Answer: 75th term

Step-by-step explanation:

If you look at the first terms, you can see that we're subtracting 12 from the previous term to get the number. Knowing this, we can write an expression for the nth term. The expression would be -12n + 20. Since this specific term has value of -880, we set -880 equal to the value of -12n+20. By setting your equation like this -12n + 20 = -880 and solving, you get n = 75, which means the 75th term has a value of -880.

Answer:

A) (√3-√2)/(√3+√2)

Step-by-step explanation:

i think so

Answer: (3, 18)

Step-by-step explanation: Where the lines corss the x does not go over 10 so the only other option is a 3. If you cut the box hori in half in you mind, the top half being 15-20 and the bottom half bring 10-14, then you can see the lines cross on the top half. Meaning it’s at 18 not 12.

Answer:

45

Step-by-step explanation:

a44 = 2 + (43 × 1) = 2 + 43 = 45

Answer:

(0.5,3.5)

Step-by-step explanation:

First, we can draw the image, as shown. The diagonals in the rectangle are the following lines:

from (-2,9) to (3,-2)

from (-5, 6) to (6,1)

To find where they intersect, we can start by making an equation for the lines. For an equation y=mx+b, m represents the slope and b represents the y intercept, or when x=0

For the first line, from (-2,9) to (3,-2), we can calculate the slope by calculating the change in y/change in x = (y₂-y₁)/(x₂-x₁). If (3,-2) is (x₂,y₂) and (-2,9) is (x₁,y₁), our slope is

(-2-9)/(3-(-2)) = -11/5

Therefore, our equation is

y= (-11/5)x + b

To solve for b, we can plug a point in, like (3,-2). Therefore,

-2=(-11/5)*3+b

-2=-33/5+b

-10/5=-33/5+b

add 33/5 to both sides to isolate b

23/5=b

Our equation for one diagonal is therefore y=(-11/5)x+23/5

For the second line, from (-5, 6) to (6,1), if (6,1) is (x₁,y₁) and (-5,6) is (x₂,y₂), the slope is (1-6)/(6-(-5)) = -5/11 . Plugging (6,1) into the equation y=(-5/11)x+b, we have

1=(-5/11)*6+b

11/11 = -30/11 + b

add 30/11 to both sides to isolate b

41/11 = b

our equation is

y = (-5/11) x + 41/11

Our two equations are thus

y = (-5/11) x + 41/11

y=(-11/5)x+23/5

To find where they intersect, we can set them equal to each other

(-11/5)x+23/5 = y = (-5/11) x + 41/11

(-11/5)x + 23/5 = (-5/11)x + 41/11

subtract 23/5 from both sides as well as add 5/11 to both sides to make one side have only x values and their coefficients

(-11/5)x + (5/11)x = 41/11-23/5

11*5 = 55, so 55 is one value we can use to make the denominators equal.

(-11*11/5*11)x+(5*5/11*5)x=(41*5/11*5)-(23*11/5*11)

(-121/55)x+(25/55)x = (205/55) - (253/55)

(-96/55)x = (-48/55)

multiply both sides by 55 to remove the denominators

-96x=-48

divide both sides by -96 to isolate x

x=-48/-96=0.5

plug x=0.5 into a diagonal to see the y value of the intersection

(-11/5)x + 23/5 = y = (-11/5)* 0.5 + 23/5 = 3.5

Answer:

80m

Step-by-step explanation:

(20x2) =40m + 40m= 80m

Answer:

see your answer in pic

mark me brainlist

Step-by-step explanation:

Answer:

x = 46.9

Step-by-step explanation:

Since this is a right triangle, we can use trig functions

sin theta = opp / hyp

sin  54 = x / 58

58 sin 54 =x

x=46.92298

To the nearest tenth

x = 46.9

Answer:

C

Step-by-step explanation:

You are correct

*Per something means multiplication*

20 per 4 weeks = 20 × 4

Answer:

x = 10

Step-by-step explanation:

7x - 15 = 4x + 15

7x - 4x = 15 + 15

3x = 30

x = 10

Answer:

x = 10

Step-by-step explanation:

Given that AC and BD are congruent , then

7x - 15 = 4x + 15 ( subtract 4x from both sides )

3x - 15 = 15 ( add 15 to both sides )

3x = 30 ( divide both sides by 3 )

x = 10

Answer:

m(∠C) = 18°

Step-by-step explanation:

From the picture attached,

m(arc BD) = 20°

m(arc DE) = 104°

Measure of the angle between secant and the tangent drawn from a point outside the circle is half the difference of the measures of intercepted arcs.

m(∠C) = [tex]\frac{1}{2}[\text{arc(EA)}-\text{arc(BD)}][/tex]

Since, AB is a diameter,

m(arc BD) + m(arc DE) + m(arc EA) = 180°

20° + 104° + m(arc EA) = 180°

124° + m(arc EA) = 180°

m(arc EA) = 56°

Therefore, m(∠C) = [tex]\frac{1}{2}(56^{\circ}-20^{\circ})[/tex]

m(∠C) = 18°

Answer:

C. 36π units²

Step-by-step explanation:

Surface area of a sphere: 4πr²

[tex]4\pi r^2\\4\pi (3)^2\\4\pi (9)\\36\pi[/tex]