Factoring Guide 1. Check to see how many ‘terms’ are in the polynomial. 2. Identify what types of factoring can be applied to the number to terms you have counted. Always check for a common factor first!! NUMBER OF TERMS TYPE OF FACTORING EXAMPLES a) Common Factoring 4r 2t − 24r 3t 2u = b) Difference of Squares Pattern: a 2 − b 2 = (a − b )(a + b ) 49a 2 − 16r 2 = a) Common Factoring 8a 2 − 24a + 40ab = b) Trinomial Pattern: x 2 + bx + c x 2 + 4x − 32 c) Trinomial Pattern: ax 2 + bx + c 6x 2 + 5x − 6 Two Three d) Perfect Square Trinomial a 2 + 2ab + b 2 1) Pattern: = (a + b )2 a 2 − 2ab + b 2 2) Pattern: = (a − b )2 Four a) Common factoring b) Grouping for a common factor - group (two terms) and (two terms) c) Grouping for a Difference of Squares - group (three terms) and (one) -three terms are a trinomial square 1) 9x 2 + 12xy + 4y 2 2) 16x 2 − 40xy + 25y 2 ax − by + bx − ay = = = a 2 − 2ab + b 2 − 25 = = =