How do you simplify (x+5)/(x-3)*(7x^2 - 21x) / (7x)?

1 Answer
Sep 21, 2015

x+5

Explanation:

Completely factor out all expressions. You can factor out 7x from (7x^2-21x).

(x+5)/(x-3)*(7x^2-21x)/(7x)

=(x+5)/(x-3)*[(7x)(x-3)]/(7x)

=[(x+5)(7x)(x-3)]/[(7x)(x-3)]

After you have factored everything out, cancel factors that appear in both the numerator and the denominator. In this problem, 7x and (x-3) appear in both the numerator and denominator, so you can cancel them.

[(x+5)cancel((7x))cancel((x-3))]/[cancel((7x))cancel((x-3))]

=(x+5)/1

=x+5