How to solve each equation by completing a square - 4x^2+10x-40=-9x^2

Answer:x=2,-4

x = - 4 or 2

Step-by-step explanation:

-4x² + 10x - 40 = - 9x²

First, move the x terms to one side and the constant to the other.

5x² + 10x = 40

Divide by the leading coefficient:

x² + 2x = 8

Take half of the b coefficient, square it, then add to both sides.

(2/2) ² = 1

x² + 2x + 1 = 8 + 1

x² + 2x + 1 = 9

Factor the perfect square:

(x + 1) ² = 9

Solve for x:

x + 1 = ±3

x = - 1 ± 3

x = - 4 or 2