Aline parallel to a triangle's side splits  ab  into lengths of x - 7 and x - 3. the other side,  ac, is split into lengths of x and x + 12. what is the length of ac?

a)21b)33c)54d)212

Mr. brettler is hanging up a 5-foot tall rectangular welcome sign in the gym. he has drawn a sketch on a coordinate grid. he has the lower vertices of the sign at (9, –3) and (–6, –3). where would the upper vertices be on the grid?