Question

How do you factor `12x^2 + 20x - 25`?

Answer 1

Factor: `y = 12x^2 + 20x - 25`

Explanation:

`y = 12x^2 + 20x - 25 =` a(x - p)(x - q) (1). I use the new AC Method (Google, Yahoo Search)
Converted `y' = x^2 + 20x - 300 =` (x - p')(x - q')
a and c have different signs.
Factor of ac = -300 -> ...(-5, 60)(-10, 30). This sum is 20 = b.
Then p' = -10 and q' = 30
Then, `p = (p')/a = -10/12 = -5/6` and `q = (q')/a = 30/12 = 5/2`

Factor form: `y = 12(x - 5/6)(x + 5/2) = (6x - 5)(2x + 5)`