Adding and Subtracting rational Expressions

A rational expression is said to be in lowest terms if the numerator and denominator ________________

• have common factor

• have no common factor except 1

• can be cancelled out

• are equal to 1

 $\frac{3}{10x^3y^4},\ \frac{2}{15x^2y^2}$ 

 Find the LCD of the expressions above

•  $150x^5y^6$  

•  $15x^2y^2$  

•  $30x^3y^4$  

•  $5x^3y^2$  

 $\frac{9}{4y^2}\ -\ \frac{1}{4y^2}$  
Subtract and simply the result.

•  $\frac{8}{4y^2}$  

•  $\frac{2}{y^2}$  

•  $\frac{5}{2y^2}$  

• undefined

 $\frac{2}{a},\ \frac{6a}{ab},\ \frac{1}{a^2}$  

Find the LCD of the expressions above

•  $a^2b$  

•  $ab$  

•  $ab^2$  

•  $a^2b^2$  

 $\frac{h}{h\ -\ k}\ +\ \frac{k}{k\ -\ h}$  
Add and simplify the result.

•  $\frac{h\ +\ k}{h\ -\ k}$  

•  $\frac{hk}{h\ -\ k}$  

•  $\frac{h\ +\ k}{k\ -\ h}$  

• 1

 $\frac{4}{d^2}\ +\ \frac{5}{d}$  

•  $\frac{4\ +\ 5d}{d^2}$  

•  $\frac{9}{d^2}$  

•  $\frac{9}{d}$  

•  $\frac{4d\ +\ 5}{d^2}$  

 $\frac{11}{3f}\ +\ \frac{9}{5f^2}\ =\ \frac{55f\ +\ 27}{15f^2}$  

True or False.

• True

• False

 $\frac{k\ -\ 6}{5}+\frac{4\ -\ k}{6}\ =\ \frac{k\ -\ 16}{30}$  

True or False.

• True

• False