Use square method to solve this quadratic equation:X^2+8x=0

Answer 1

Don't know what you mean by "square method", I will assume you
mean "completing the square"

x^2 + 8x = 0
x^2 + 8x + 16 = 16
(x+4)^2 = 16
x+4 = ± 4
x+4 = 4 ----> x = 0
x+4 = -4 ----> x = -8

A more practical would have been to simply use factoring:
x^2 + 8x = 0
x(x+8) = 0
x = 0 , x = -8