Step-by-step solving: Factoring
1. x² + 5x = 0
x(x + 5) = 0
x + 5 = 0
x = -5
2. 7x² + 21x = 0
7x(x + 3) = 0
x + 3 = 0
x = -3
3. 16x² = 12x
16x² - 12x = 0
4x(4x - 3) = 0
4x - 3 = 0
4x = 3
x = [tex]\frac{3}{4}[/tex]
4. -4x² = 6x
-4x² - 6x = 0
The first term (ax²) must not be ≤ 0. Therefore (∴)...
4x² + 6x = 0
2x(2x + 3) = 0
2x + 3 = 0
2x = -3
x = [tex]-\frac{3}{2}[/tex]
5. x² + 8x + 12 = 0
(x + 2)(x + 6) = 0
x + 2 = 0
x = -2
x + 6 = 0
x = -6
