Algebra: Chapter 6, Lesson 3, page 270
Trinomial Squares
We are going backward again, using the properties:
- `(a + b)(a + b) = a^2 + 2ab + b^2 = (a + b)^2`
- `(a – b)(a – b) = a^2 – 2ab + b^2 = (a – b)^2`
For a trinomial square to factor, we must make sure that:
- 2 of the terms must be squares, `a^2` and `b^2`
- There must be NO MINUS sign before the `a^2` and `b^2`
- If we multiply `a` and `b` and double the result, we get the 3rd term, `2ab` or its additive inverse `- 2ab`.
Sometimes, we can also factor out a coefficient in front of the `a^2`, like `2a^`. We MIGHT be able to factor out the `2` before we start the trinomial determination.
Here is a purplemath link that describes trinomial squares, scroll down about 1/2 way to get to the information.