Adding and Subtracting Rational Expressions

What is the least common multiple of  $25x$  and  $15x$  ?

•  $5x$  

•  $5x^2$  

•  $75x$  

•  $375x^2$  

What is the least common multiple of  $16x^{2\ }$  and  $24x$  ?

•  $384x^{3\ }$  

•  $48x^{2\ }$  

•  $48x$  

•  $8x$  

What is the least common multiple of  $6x$  and  $2\left(x-1\right)$  ?

•  $12x\left(x-1\right)$  

•  $6\left(x-1\right)$  

•  $6x\left(x-1\right)$  

•  $2\left(x-1\right)$  

What is the least common multiple of  $9x\left(x-1\right)$  and  $12x$  ?

•  $3x$  

•  $36x^2\left(x-1\right)$  

•  $108x\left(x-1\right)$  

•  $36x\left(x-1\right)$  

What is the least common multiple of  $5\left(x+4\right)$  and  $\left(x^2-16\right)$  ?

•  $5\left(x-4\right)\left(x+4\right)$  

•  $5\left(x+4\right)$  

•  $\left(x+4\right)\left(x-4\right)$  

•  $\left(x+4\right)$  

What is the least common multiple of  $\left(18x-12\right)$  and  $\left(6x-4\right)$  ?

•  $2\left(3x-2\right)$  

•  $6\left(3x-2\right)$  

•  $\left(3x-2\right)$  

•  $\left(18x-12\right)\left(6x-4\right)$  

What is the least common multiple of  $\left(x^2-6x-16\right)$  and  $4\left(x+2\right)$  ?

•  $\left(x+2\right)$  

•  $4\left(x+2\right)$  

•  $4\left(x-8\right)$  

•  $4\left(x+2\right)\left(x-8\right)$  

What is the least common multiple of  $\left(x^2-8x+15\right)$  and  $\left(6x-18\right)$  ?

•  $6\left(x-3\right)$  

•  $\left(x-3\right)\left(x-5\right)$  

•  $6\left(x-3\right)\left(x-5\right)$  

•  $\left(x-3\right)$  

Rewrite $\frac{4}{3x}$  with a denominator of  $12x^2$  

•  $\frac{4}{12x^2}$  

•  $\frac{4x}{12x^2}$  

•  $\frac{16}{12x^2}$  

•  $\frac{16x}{12x^2}$  

Rewrite $\frac{x}{2\left(x-1\right)}$  with a denominator of  $2\left(x-1\right)\left(x+2\right)$  

•  $\frac{x}{2\left(x-1\right)\left(x+2\right)}$  

•  $\frac{x+2}{2\left(x-1\right)\left(x+2\right)}$  

•  $\frac{x^2+2x}{2\left(x-1\right)\left(x+2\right)}$  

•  $\frac{x^2+2}{2\left(x-1\right)\left(x+2\right)}$