• Using Trial factors
o If the terms of the trinomial do not have a common factor , then the terms of a
binomial
factor cannot have a common factor
o When the constant term is positive , the constant terms of the binomials have
the same sign
as the coefficient of x
o When the constant term is negative , the constant terms of the binomials have
opposite sign .
Ex. Factor by using trial factors:
• Factor 
by grouping
o First find two factors of ac whose sum is b
o Use the two factors to rewrite the middle term of the trinomial as the sum of
two terms.
o Use factoring by grouping
Ex. Factor by grouping:
HW page 439 # 3 – 67 every other odd, 75, 79, 81, 85, 95, 101, 115, 123, 129,
133
