2 angles are complementary. the measure of one angle is 15 degrees more than twice the other. What is the measure of the smaller angle?

Here's how to set this up.  First you remember that complementary angles add up to 90 degrees, right?

So then you set up your equation using your other data.  We'll call one angle's measure "x" -- that will be the smaller one.  And we know that the other one is 15 degrees more than twice x.  How do you put that in mathematical terms?  Twice x is 2x, 15 more is +15.

So that gives us

90 = x + 2x + 15

So now we need to get all the x's on one side and the numbers on the other.  Subtract 15 from both sides.

x + 2x = 75 or 3x = 75.

Now you have to divide both sides by 3 so as to solve for x

x = 25

To check this, plug the numbers into the original equation.

15 more than twice 25 is 50+15 = 65.

So one of our angles is 25 degrees and the other is 65 (twice 25 + 15).  Those add up to 90 degrees so they're complementary.