1. ## Solving Variation Equations

Hey everyone... I'm having problems with two questions from my Algebra 2 book. The questions are about Variation Equations.

There are two types of problems that I want to go over so any help is appreciated. Thanks.
---------------------------------

9. y varies directly as x. If x = 4, then y = -12. Find y when x = -7.

11. y varies inversely as the cub of x. If x = 4, y = -1/16. Find y when x = 1/2.

2. Originally Posted by CzWJF41
Hey everyone... I'm having problems with two questions from my Algebra 2 book. The questions are about Variation Equations.

There are two types of problems that I want to go over so any help is appreciated. Thanks.
---------------------------------

9. y varies directly as x. If x = 4, then y = -12. Find y when x = -7.

11. y varies inversely as the cub of x. If x = 4, y = -1/16. Find y when x = 1/2.
"Varies directly" implies that $-12=k(4)$

"Varies inversly" implies $-12=\frac{k}{4}$

Where k is constant.