For 48 points ! show/explain your answer and work

c  This is the direct variation

Step-by-step explanation:

The equation for direct variation is y= kx

Solving this for k

y/x =k

So y/x must be a constant

a.  9/3 =3

2/7 does not =3  so this is not a direct variation

b 1/2 = .5

-3/6 = -.5

This is not the same so this is not a direct variation

c.  27/9 =3

18/6 =3

9/3 =3

This is a direct variation with a constant of 3

d 5/-7 = -5/7

1/-3 = -1/3

This is not the same so this is not a direct variation

C

Step-by-step explanation:

The equation you are looking for must look something like y = k*x

The easiest way to find it is to try 2 points to see if k would be equal in both cases. Do this for each choice.

A

k is not the same in both case. A is not the  answer.

B

Using the steps above

B is not the answer.

C

C is the answer

You can try D yourself

use the power rule  

( a b ) n = a n b n

to distribute the exponent.

apply the product rule to  

3 x 2 y 3 . ( 3 x 2 ) 2 ( y 3 ) 2

apply the product rule to  

3 x 2 . 3 2 ( x 2 ) 2 ( y 3 ) 2

raise  

3

to the power of  

2 . 9 ( x 2 ) 2 ( y 3 ) 2 multiply the exponents in   ( x 2 ) 2

.

apply the power rule and multiply exponents,  

( a m ) n = a m n . 9 x 2 ⋅ 2 ( y 3 ) 2

multiply  

2   by   2 . 9 x 4 ( y 3 ) 2

multiply the exponents in  

( y 3 ) 2 .

apply the power rule and multiply exponents,  

( a m ) n = a m n . 9 x 4 y 3

⋅

2

multiply  

3   by   2 . 9 x 4 y 6

step-by-step explanation:

entering that problem on the tube might get you an answer