# How do you factor trinomials?

##### 1 Answer

Extension to factoring, when the trinomials do not factor into a square (it also works with squares).

**Sum-product-method**

Say you have an expression like

Then you try to write

You can write

*Sums* of these are

*Differences* are

Check your answer!

It's a bit harder when one or two of the numbers are negative, let's take

Same as the first, only now both factors are negative

**Extra**

If the last number (*difference* of the factors. Check the next one yourself:

And now try: