Question

Solve 9x−y=45 for y.

Answer 1

So to solve for y, we need to get y alone on one side of the equation. So we are going to subtract 9x from both sides of the equation to get:

$-y=-9x+45$

And since y is negative, we are going to divide both sides by -1 in order to make the y positive:

$y=9x-45$