Answer:
(x + 10)² = 4
Explanation:
Given
2x² + 192 = - 40x ( add 40x to both sides )
2x² + 40x + 192 = 0 ( subtract 192 from both sides )
2x² + 40x = - 192 ( divide through by 2 )
x² + 20x =- 96
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(10)x + 100 = - 96 + 100
(x + 10)² = 4