Question

Simplify and select the answer with the appropriate restrictions for the variables.

x^2-25 / x + 5

A) x - 5, (x ≠ 5)
B) x - 5, (x ≠ -5)
C) x + 5, (x ≠ 5)
D) x + 5, (x ≠ -5)

Answer 1

Before simplifying realize that division by zero is undefined, as it is not a real value and has no meaning. So x cannot equal -5.

The numerator is a difference of squares of the form:

(a^2-b^2) which always factors to (a-b)(a+b) so

(x-5)(x+5)/(x+5) the (x+5)s cancel leaving:

(x-5), and since x cannot equal -5

A) x-5, (x≠-5)