Question

y varies inversely with x, and x = -10 when y = 60. Find the inverse variation equation and use it to find the value of y when x = 15.
-75
-90
-40
-30

Answer 1

inverse relationship is:

y = k/x

they are asking you to find the value of k, then use the value of k to find y when x = 15 (that sounds confusing)

so to start, find k by plugging in the given values at the beginning of the problem:

60 = k/-10
-6 = k

now you have

y = -6/x

you should be able to solve for y knowing x = 15 here

Answer 2

actually, i did that wrong

it should be

y = k/x
60 = k/-10
-600 = k

which gives you a final equation of

y = -600/x

knowing x = 15 here, you should be able to find the correct answer