Question

(x+2)(x-16)+(x+7)^2=89(x+2)(x-16)+(x+7)^2=89

Answer 1

(x+2)(x-16)+(x+7)^2=89
(x+2)(x-16) + (x+7).(x+7) = 89
x² -16x +2x -32 +x² +7x +7x +49 = 89
x² +x² -16x +2x+7x+7x -32-89+49=0
2x² -16x +16x -121+49=0
2x² -76=0 :2
x² -36=0
x²= +36
x=± √36
x=± 6

S= +6 e -6