Answer :
x² - 8x = 65
x² - 8x + 16 = 65
x² - 8x + 16 - 65 = 65 - 65
x² - 4x - 4x + 16 - 65 = 0
x(x) - x(4) - 4(x) + 4(4) - 65 = 0
x(x - 4) - 4(x - 4) - 65 = 0
(x - 4)(x - 4) - 65 = 0
(x - 4)² - 65 = 0
It is actually (x - 4)² - 65.
x² - 8x + 16 = 65
x² - 8x + 16 - 65 = 65 - 65
x² - 4x - 4x + 16 - 65 = 0
x(x) - x(4) - 4(x) + 4(4) - 65 = 0
x(x - 4) - 4(x - 4) - 65 = 0
(x - 4)(x - 4) - 65 = 0
(x - 4)² - 65 = 0
It is actually (x - 4)² - 65.