How to use it
- List factor pairs of c.
- Find the pair whose sum is b.
- Write (x+m)(x+n).
See it in action
x²+7x+12 → 3 and 4 → (x+3)(x+4).
How to verify it
Expand to recover x²+7x+12.
Common mistake
For leading coefficients other than 1, use a more general factoring method.