X(x-7)=(x+9)2 помогите плз

Question

X(x-7)=(x+9)2 помогите плз

Answer 1

2x-7x=2x+18
-9x=18
x=-2

Comments

(x+9) во 2 степени.

Answer 2

X^2-7x=2x+18
x^2-7x-2x=18
x^2-9x=18
(x-3)(x+3)=18
x-3=18 x+3=18
x=21    x=15