Math
posted by Christopher on .
Mr Shen wished to enter the orange kite competition with an innovative kite of his own design. He did tests that showed an irregular quadrilateral design was best. The longest side (A) was twice the length of the shortest side (C). Side B was one and onehalf times the shortest side (C). Side D needed to be 4" (4 inches) longer then side C. If the competition required that the perimeter of your kite must be 81", what were the dimensions of Mr. Shen's Kite?
Side C  x
side A  2x
side B 1.5x
side D  x+4
x + 2x + 1.5x + x+4 = 81
5.5x = 77
x = 14
Now I got the answers for A and B
A=28
B=21
I need help for answers C and D

all that algebra went ok, and you have trouble with arithmetic?
C = x = 14
D = x+4 = 18
A+B+C+D = 28+21+14+18 = 81