How to do do trinomials in a easy way

Multiply the First terms
Multiply the Outside terms
Multiply the Inside term
Multiply the Last terms
Simplify

Understand factoring.

Write a space for the answer in FOIL form.
Don't write + or - between the blank terms yet, since we don't know which it will be.

Fill out the First terms.

Use factoring to guess at the Last terms.

Test which possibilities work with Outside and Inside multiplication.

Use simple factoring to make more complicated problems easier.

Look for trickier factors.

Solve problems with a number in front of the x^2.

Use substitution for higher-degree trinomials.

Check for prime numbers.

Check to see if the trinomial is a perfect square.

Check whether no solution exists.

If both binomials have the same variables to the same powers, then it is true. In general, multiplying binomials gives four terms, one corresponding to each letter of the FOIL acronym. So, you only get a trinomial when the O and I terms combine.

The first digit is in the middle school 100s place