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4 years ago

How do I work this out?

Mathematics

1 answer:

adell [148]4 years ago

6 0

You use the Pythagorean theorem.
(1)^2 + (x)^2 = (3)^2
1 + x^2 = 9
x^2 = 9-1
x^2 = 8
Square root of x^2 = square root of 8
x = Square root of 8

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Pls help and thank you!!

nirvana33 [79]

Your answer is A.

why:

because if the y value changes then your vertical will change. if your x changes than your horizontal will change. if it’s compressed, your x value is less than 1.

8 0

3 years ago

Solve for x <br> m= x+n <br> p

umka21 [38]

The answer will be
x=m-n

6 0

3 years ago

The points A-1,-9) and K(5,1) are endpoints of a diameter of circle 5. Which equation represents circle S?

Lilit [14]

Answer:

Step-by-step explanation:

if (x1,y1) and (x2,y2) are the extremities of diameter,then eq. of circle is

(x-x1)(x-x2)+(y-y1)(y-y2)=0

reqd. eq. is (x+1)(x-5)+(y+9)(y-1)=0

$x^{2} +x-5x-5+y^2+9y-y-9=0\\x^{2} -4x+y^2+8y-14=0\\compare with x^2+y^2+2gx+2fy+c=0\\center (-g,-f) \\radius r=\sqrt{g^2+f^2-c}$

center is (2,-4)

r=√(2²+(-4)²-(-14))

=√(4+16+14)

=√(34)

eq. of circle is (x-2)²+(y+4)²=34

(x²-4x)+(y²+8y)=14

(x²-4x+4)+(y²+8y+16)=14+4+16

(x-2)²+(y+4)²=34

4 0

4 years ago

What equation represents a line that when if graphed, passes through the points (0, -1) and

Keith_Richards [23]

Y= 2x-1
Explanation: First, you find slope. If the first point it x-axis point is 0 and the second x-axis point is 1 then you already know the answer is over 1, so you have to figure out how many up you are going on the y-axis from -1 to 1. Which is 2, so your slope is 2/1 or just 2. Next, you find your y-intercept, which is where the line crosses the y-axis, and the easy way to find this is finding what y is equal to when x is equal to 0, in the problem you are told (0, -1) as a point, so they gave you your y-intercept right there, which is -1. Finally you right the equation in slip intercept form (y= mx+b) which is y= 2x-1

5 0

3 years ago

A report on consumer financial literacy summarized data from a representative sample of 1,664 adult Americans. Based on data fro

daser333 [38]

Answer:

a. The 95% confidence interval for the proportion of all adult Americans who would give themselves a grade of A or B on their financial knowledge of personal finance is (0.54, 0.588). This means that we are 95% sure that the true proportion of all adult Americans who would give themselves a grade of A or B on their financial knowledge of personal finance is between these two bounds.

b. Because this confidence interval is entirely above 0.5, the interval is consistent with the statement that a majority of adult Americans would give themselves a grade of A or B.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

Sample of 1,664 adult Americans, 939 people in the sample would have given themselves a grade of A or B in personal finance.

This means that $n = 1664, \pi = \frac{939}{1664} = 0.5643$

95% confidence level

So $\alpha = 0.05$ , z is the value of Z that has a pvalue of $1 - \frac{0.05}{2} = 0.975$ , so $Z = 1.96$ .

The lower limit of this interval is:

$\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.5643 - 1.96\sqrt{\frac{0.5643*0.4357}{1644}} = 0.54$

The upper limit of this interval is:

$\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.5643 + 1.96\sqrt{\frac{0.5643*0.4357}{1644}} = 0.588$

The 95% confidence interval for the proportion of all adult Americans who would give themselves a grade of A or B on their financial knowledge of personal finance is (0.54, 0.588). This means that we are 95% sure that the true proportion of all adult Americans who would give themselves a grade of A or B on their financial knowledge of personal finance is between these two bounds.

(b) Is the confidence interval from part (a) consistent with the statement that a majority of adult Americans would give themselves a grade of A or B?

Yes, because the confidence interval is entirely above 0.5.

Because this confidence interval is entirely above 0.5, the interval is consistent with the statement that a majority of adult Americans would give themselves a grade of A or B.

8 0

3 years ago