Chapter 7 Factoring
1. Finding prime factors-
Factors of 48 = (1)(48) = (2)(24)=(16)(3) = (4)(12) = (4)(4)(3); prime factors- (24)(3)
Finding the greatest common factor and factoring out- Ex. 4a2 -20a = 4a(a -5)
Factoring by grouping
2. Factoring trinomials- Ex x2 + 3x + 2 can be factored as (x +2)(x+1) check it by FOIL to see whether it
gives the original expression.
3. Special factorizations- Difference between two squares a2 - b2 = (a + b)(a - b)
a2 + 2ab + b2 = (a + b)2
a2 - 2ab + b2 = (a - b)2
4. Solving quadratic equations by factoring:
Ex. To solve x2 -3x + 2 = 0
Find factors (x - 2)(x - 1) = 0; therefore x - 2 = 0 and/or x - 1 = 0
Giving x = 2 or x = 1 as the solutions
5. Applications of quadratic equations