### Home > AC > Chapter 12 > Lesson 12.1.1 > Problem12-5

12-5.

Use your factoring shortcuts to simplify the following expressions.

1. $\frac { x ^ { 2 } - 9 } { x ^ { 2 } - 6 x + 9 }$

1. $\frac { 2 x + 5 } { 4 x ^ { 2 } - 25 } \cdot \frac { 2 x - 5 } { x + 7 }$

1. $\frac { x ^ { 2 } + x - 20 } { x ^ { 2 } - 16 } \cdot \frac { x ^ { 2 } + 9 x + 20 } { x ^ { 2 } + 10 x + 25 }$

1. $\frac { x ^ { 2 } + 12 x + 36 } { x ^ { 2 } - 25 } \div \frac { x + 6 } { x + 5 }$

$\frac { ( x + 3 ) ( x - 3 ) } { ( x - 3 ) ( x - 3 ) }$

$\frac { ( x - 3 ) } { ( x - 3 ) } = 1$

$\frac { ( x + 3 ) } { ( x - 3 ) }$

$\frac { 2 x + 5 } { ( 2 x + 5 ) ( 2 x - 5 ) } \cdot \frac { 2 x - 5 } { x + 7 }$

$\frac { ( 2 x + 5 ) ( 2 x - 5 ) } { ( 2 x + 5 ) ( 2 x - 5 ) ( x + 7 ) }$

Look for ones.

See part (b).