What is the simplified form of (x^2-25)/(x-5)?

1 Answer
Sep 13, 2015

(x^2-25)/(x-5) = x+5 with exclusion x != 5

Explanation:

Use the difference of squares identity:

a^2-b^2 = (a-b)(a+b)

to find:

(x^2-25)/(x-5) = (x^2-5^2)/(x-5) = ((x-5)(x+5))/(x-5)

= (x-5)/(x-5)*(x+5) = x+5

with exclusion x != 5

Note that if x = 5 then both (x^2-25) and (x-5) are 0, so (x^2-25)/(x-5) = 0/0 is undefined.