### Home > INT3 > Chapter 12 > Lesson 12.2.1 > Problem12-79

12-79.

Add or subtract and simplify each of the following expressions.

Factor after adding or subtracting.

1. $\frac { x ^ { 2 } } { x - 5 } - \frac { 25 } { x - 5 }$

1. $\frac { a ^ { 2 } } { a + 5 } + \frac { 10 a + 25 } { a + 5 }$

1. $\frac { x ^ { 2 } } { x - y } - \frac { 2 x y - y ^ { 2 } } { x - y }$

1. $\quad \frac { x } { x + 1 } + \frac { 1 } { x - 1 }$

In part (d), notice that the denominators are different. Find a common denominator before adding.

$\frac{x^2+1}{x^2-1}$