How do you factor #50+5a - a^2#?

1 Answer
May 15, 2015

First notice that #a=10# is a zero of this polynomial, since if #a=10# we have

#50+5a-a^2 = 50+5*10-10^2 = 50+50-100 = 0#

So #(10-a)# is one factor.

Comparing coefficients, the other is #(5+a)#, with #-5# being another zero of the polynomial.

#(10-a)(5+a) = 50-5a+10a-a^2 = 50+5a-a^2#