Answer:
(x - 4)² = 9
Step-by-step explanation:
x² - 8x + 7 = 0 ( add 7 to both sides )
x² - 8x = - 7
to complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(- 4)x + 16 = - 7 + 16
(x - 4)² = 9 ← equation to be solved
take the square root of both sides
x - 4 = ± [tex]\sqrt{9}[/tex] = ± 3 ( add 4 to both sides )
x = 4 ± 3
then solutions are
x = 4 - 3 = 1 or x = 4 + 3 = 7
