Question 305983
X^2+(2X-1)^2=(2X+1)^2
X^2+4X^2-4X+1=4X^2+4X+1
X^2+4X^2-4X^2-4X-4X+1-1=0
X^2-8X=0
X(X-8)=0
X=0
X-8=0
X=8 ANS.
8^2+(2*8-1)^2=(2*8+1)^2
64+(16-1)^2=(16+1)^2
64+15^2=17^2
64+225=289
289=289