Week 10 – Factoring Polynomials Review
Factoring is writing an expression as a product of factors.
Common?
Difference of squares
Pattern
Easy
Ugly
ex. Factor x2 – 6x -16
Find two numbers whose product is -16 and whose sum is -6: 2 and -8.
So, (x + 2) (x – 8)
ex. Factor 3y(y + 2) – 9 (y + 2)
To easily factor this, replace y + 2 with a variable such as a.
Now factor 3ya – 9a —> has common factor of 3 and a
3a(y – 3)
Substitute a = y + 2 in the expression above.
So, 3(y + 2)(y – 3)