–32 + = 2(x2 + 10x + 25)
18 = 2(x + 5)2
9 = (x + 5)2
± = x + 5
x = –2 or x =
Answer:
x = - 2 or x = - 8
Step-by-step explanation:
Given
2(x² + 10x) = - 32 ( divide both sides by 2 )
x² + 10x = - 16
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(5)x + 25 = - 16 + 25
(x + 5)² = 9 ( take the square root of both sides )
x + 5 = ± = ± 3 ( subtract 5 from both sides )
x = - 5 ± 3, thus
x = - 5 + 3 = - 2 or x = - 5 - 3 = - 8