Y=x ^2-9x+20 what is the answer bc rn I'm clueless

The slope of a line is 5. A (2, 1) is a point on the line. Another point, B, on the line has y=81. What is the x-value at this p

HACTEHA [7]

The x-value at the point, denoted by d, is 18

<h3>Slope of a line </h3>

From the question, we are to determine the x-value at point B on the line

Given the points (x₁, y₁) and (x₂, y₂) on a line.

The slope, m, of a line with two points (x₁, y₁) and (x₂, y₂) on the line is given by the formula

m = (y₂ - y₁)/(x₂ - x₁)

From the given information,

Point A is (2, 1)

Point B is (d, 81)

That is,

x₁ = 2

y₁ = 1

x₂ = d

y₂ = 81

and

slope, m = 5

Thus,

5 = (81 - 1) / (d - 2)

5 = 80/(d -2)

5(d - 2) = 80

5d - 10 = 80

5d = 80 + 10

5d = 90

d = 90/5

d = 18

Hence, the x-value at the point, denoted by d, is 18

Learn more on Slope of a Line here: brainly.com/question/19012287

#SPJ1

4 0

2 years ago

Quick! Help! Find the area of the composite figure

Sonbull [250]

Answer:

`100 ft

Step-by-step explanation:

5 0

3 years ago

1 over 4 minus 1 over 8

fgiga [73]

I hope this helps you

1^4-1^8

1-1

0

8 0

3 years ago

A random sample of 500 adult residents of Maricopa County found that 356 were in favor of increasing the highway speed limit to

zzz [600]

Answer:

$z=1.04$

$p_v =2*P(Z>1.04)\approx 0.298$

Comparing the p value with the significance level given $\alpha=0.05$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can't say that the proportion of people in favor of the increased speed limit not differs significantly between the two groups.

Step-by-step explanation:

1) Data given and notation

$X_{PC}=297$ represent the number of residents of Pima County in favor of the increased speed limit

$X_{MC}=356$ represent the number of residents of Maricopa County in favor of the increased speed limit

$n_{PC}=400$ sample of Pima County selected

$n_{MC}=500$ sample of Maricopa County selected

$p_{PC}=\frac{297}{400}=0.743$ represent the proportion of residents of Pima County in favor of the increased speed limit

$p_{MC}=\frac{356}{500}=0.712$ represent the proportion of residents of Maricopa County in favor of the increased speed limit

z would represent the statistic (variable of interest)

$p_v$ represent the value for the test (variable of interest)

$\alpha=0.05$ significance level given

2) Concepts and formulas to use

We need to conduct a hypothesis in order to check if is there is a difference in the support for in increasing the speed limit between the residents of the two counties, the system of hypothesis would be:

Null hypothesis: $p_{PC} - p_{MC}=0$

Alternative hypothesis: $p_{PC} - \mu_{MC} \neq 0$

We need to apply a z test to compare proportions, and the statistic is given by:

$z=\frac{p_{PC}-p_{MC}}{\sqrt{\hat p (1-\hat p)(\frac{1}{n_{PC}}+\frac{1}{n_{MC}})}}$ (1)

Where $\hat p=\frac{X_{PC}+X_{MC}}{n_{PC}+n_{MC}}=\frac{297+356}{400+500}=0.726$

z-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.

3) Calculate the statistic

Replacing in formula (1) the values obtained we got this:

$z=\frac{0.743-0.712}{\sqrt{0.726(1-0.726)(\frac{1}{400}+\frac{1}{500})}}=1.04$

4) Statistical decision

Since is a two side test the p value would be:

$p_v =2*P(Z>1.04)\approx 0.298$

Comparing the p value with the significance level given $\alpha=0.05$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can't say that the proportion of people in favor of the increased speed limit not differs significantly between the two groups.

8 0

3 years ago

The perimeter of a rectangular pool is 312 m.

expeople1 [14]

The perimeter of a rectangle is calculated by:

$\boxed{P=width +width+length+ length}$

Remember: In a rectangle, opposite sides are equals.

If we know how much is the width, then it's just apply it to the expression:

$P=width+width+length+length\\312 =68 + 68 + length + length\\312 = 136+(2\cdot length)\\312 - 136 = 2\cdot length\\2\cdot length = 176\\length = \frac{176}{2} \\length = 88$

Therefore, the length of the pool is 88m.

3 0

3 years ago