[mszee]

Originally Posted by Chris

2(a² - ab) = a² - ab




You should get 0 from this line.

You stated a = b so if we subsitute we get 2(a² - aa) = a² - aa

Apply the basic rule of calculus that brackets, division, multiplication, ddition & subtraction must be done in that order and we get:

2(0) = 0

Thank god I am not senile yet!!!