y is 2 when x is 10. What is the value of y when x is -25?

Question

i need to find out what y is when x is -25

Answer 1

Formula for direct variation is y=kx, where k represents the constant. So, we solve for "k" first given the "x" and "y" variables.

 

Read "y varies directly as x" when y=2, x=10:

 

2 = k(10)

 

2  = k(10)

10      10

 

1

5  = k 

 

Now that you found "k" you can substitute that into equation with the other given variables:

y = (1/5)(-25)= -5