Math 300

Fraction Unit

Dr. Wilson


Corollary: (The cancellation property of integer multiplication) If a, b, and c are integers with a not zero and ab = ac, then b = c.


Proof: Assume that ab = ac but a is not 0. Then


ab - ac = 0


Factor out an a from both terms.


a(b - c) = 0


We now use the fact that if a product is 0 then one of the factors is 0. We have assumed that a is not 0, so we must conclude that


b - c = 0


b = c