Question 229017
A=2P+9
X^2=A
P=4X
REPLACE A WITH X^2 & REPLACE P WITH 4X & SOLVE FOR X THE SIDE OF THE SQUARE.
X^2=2*4X+9
X^2=8X+9
X^2-8X-9=0
(X-9)(X+1)=0
X-9=0
X=9 ANS FOR THE SIDE OF THE SQUARE.
PROOF:
9^2=2*4*9+9
81=72+9
81=81