Test 3 Section 4 #30

This one is yucky. Let’s attack it by substituting. First, we’re told that , so let’s reflect that (I’m going to use the decimal version of for simplicity):

Now, let’s solve both equations for *c*:

Because we now have two different equations with *c* isolated, we can substitute again here to get an equation that only contains *x*s and *y*s.

That translates to “*x* is *y* minus ,” so **the answer is A**.