If y=7.5 when x=0.5, find y when x=-3My algebra one teacher is horrible! I never understand anything she is saying! Please explain in simple terms!

Okay, the first thing you need to do is figure out what the relationship is between x and y.  Here's how you do that:

First, write a direct-variation formula

y = kx  where k is the constant of variation.  Plug in the y and x values that you know.

7.5 = .5k

To find for k, multiply both sides by 2 and you get k = 15

By that, we know that y is 15 times bigger than x.

So now all you have to do is plug your other value for X into that equation (y = kx).  Remember that we know that k = 15

So that gives us y = 15*-.3

And when you do the math, you get

y = -4.5