Question

What is the difference of the rational expressions below

Answer 1

$\bf \cfrac{9}{x^2}-\cfrac{2x+1}{8x}\implies \stackrel{\textit{our LCD will be }8x^2}{\cfrac{(8)9~~-~~(x)(2x+1)}{8x^2}}\implies \cfrac{72-(2x^2+x)}{8x^2} \\\\\\ \cfrac{72-2x^2-x}{8x^2}\implies \cfrac{-2x^2-x+72}{8x^2}$

Answer 2

The correct anser is A.