32*1.2=38.4 (.2 is the 20%, and the 1 adds the percent to the original cost making it a mark up)
Angles B and D are supplementary angles, so if B's angle is 30 degrees, then D's angle at y would be 150, since they have to add to 180.
In short, angle y = 150
Take DEBC a parralelogram
Parralel sides are DE and BC
THEREFORE,
1/2*(a+b)*h
1/2*(6+15)*h
1/2*(21)*h=0
10.5*h=0
h=-10.5
