Answer:
16
Explanation:
To solve a quadratic equation by using the completing the square method, the coefficient of the square term i.e x² must be one (1).
Therefore, we would have to first make the coefficient of x² to be equal to 1.
4x² + 24x + 8 = 32
We would simplify the equation;
4x² + 24x = 32 - 8
4x² + 24x = 24
Divide all through by 4;
x² + 8x = 24
The value to be added = (8/2)² = 4² = 16
x² + 8x + 16 = 8 + 16
x² + 4x + 4x + 16 = 24
x(x + 4) + 4(x + 4) = 24
(x + 4)² = 24
Taking the square root of both sides;
x + 4 = ± 4.9
x = -4 ± 4.9
x = -4 + 4.9 = 0.9
or
x = -4 - 4.9 = - 8.9
Therefore, 16 must be added to solve the quadratic equation by completing the square method.