Is y=(x/2)^2 a function?

Find the sample size required to achieve the given margin of error with SD = 51.02 and z - score = 1.96. Round your answer to th

coldgirl [10]

Answer:

The sample size required is 2500.

Step-by-step explanation:

z-score:

In function of the margin of error M, the z-score is given by:

$Z = \frac{M}{\frac{\sigma}{\sqrt{n}}} = \frac{M\sqrt{n}}{\sigma}$

In this question, we have that:

$\sigma = 51.02, M = 2, Z = 1.96$

So

$Z = \frac{M\sqrt{n}}{\sigma}$

$1.96 = \frac{2\sqrt{n}}{51.02}$

$2\sqrt{n} = 51.02*1.96$

$\sqrt{n} = \frac{51.02*1.96}{2}$

$(\sqrt{n})^2 = (\frac{51.02*1.96}{2})^2$

$n = 2500$

The sample size required is 2500.

3 0

3 years ago

What is the solution to he equation (y/y-4)-(4/y+4)=3^2/y^2-16

kicyunya [14]

Answer:

$y=\pm i \sqrt{7}$

Step-by-step explanation:

Given equation is $\frac{y}{\left(y-4\right)}-\frac{4}{\left(y+4\right)}=\frac{3^2}{(y^2-16)}$

Factor denominators then solve by making denominators equal

$\frac{y}{\left(y-4\right)}-\frac{4}{\left(y+4\right)}=\frac{3^2}{(y^2-16)}$

$\frac{y}{\left(y-4\right)}-\frac{4}{\left(y+4\right)}=\frac{9}{(y+4)\left(y-4\right)}$

$\frac{y\left(y+4\right)-4\left(y-4\right)}{\left(y-4\right)\left(y+4\right)}=\frac{9}{(y+4)\left(y-4\right)}$

$y\left(y+4\right)-4\left(y-4\right)=9$

$y^2+4y-4y+16=9$

$y^2=9-16$

$y^2=-7$

take squar root of both sides

$y=\pm \sqrt{-7}$

$y=\pm i \sqrt{7}$

Hence final answer is $y=\pm i \sqrt{7}$ .

7 0

3 years ago

A swimming pool has about 603 cubic feet of water. The pool liner has a small hole and is leaking at a rate of 1.5 cubic feet ea

Readme [11.4K]

Answer:

Ruby’s function notation V(h) describes the volume of the pool after h number of hours. Hours is the independent variable and the total volume is the dependent variable.

Step-by-step explanation:

sample response

3 0

3 years ago

Read 2 more answers

What could be the mean of the data set below be misleading? Ages of teachers: 29, 38,39,26,29,29,39,77,38,29

Vlada [557]

Add them all up, and divide by 10 so 29+38+39+26+29+29+39+77+38+29 which is 33.5

4 0

3 years ago

Write a quadratic relation in the form y = ax2 + bx + c with roots 4 and - 3 and

pochemuha

Answer:

y = 2*x^2 - 2*x - 24

Step-by-step explanation:

If we have a quadratic function with roots a and b, we can write the equation for that function as:

y = f(x) = A*(x - a)*(x - b)

Where A is the leading coefficient.

In this case, we know that the roots are: 4 and -3

Then the function will be something like:

f(x) = A*(x - 4)*(x - (-3) )

f(x) = A*(x - 4)*(x + 3)

Now we need to determine the value of A.

We also know that the graph of the function passes through the point (3, -12)

This means that:

f(3) = -12

Then:

-12 = A*(3 - 4)*(3 + 3)

-12 = A*(-1)*(6)

-12 = A*(-6)

-12/-6 = A

2 = A

Then the equation is:

y = f(x) = 2*(x - 4)*(x + 3)

Now we need to write this in standard form, so we just need to expand the equation:

y = f(x) = 2*(x^2 + x*3 - x*4 - 4*3)

y = f(x) = 2*(x^2 - x - 12)

y = f(x) = 2*x^2 - 2*x - 24

Then the relation is:

y = 2*x^2 - 2*x - 24

4 0

3 years ago