Question

$x^{2}+(x-3)^{2}=(x+3)^{2}$

Answer 1

x² + x² - 6x + 9 = x² + 6x + 9
x² - 12x = 0
x (x - 12) = 0
x = 0 ou x = 12

Answer 2

x^2 + x^2 - 6x + 9 = x^2 + 6x + 9

x^2 + x^2 - 6x + 9 - x^2 - 6x - 9 = 0

x^2 - 12x = 0

x( x - 12 ) =0

x1 = 0

x - 12 = 0

x2 = 12