Answer
$-\frac{1}{3x}$
Work Step by Step
$25x=\underline5\times\underline5\times\underline x$
$75x^2=3\times\underline5\times\underline5\times\underline x\times x$
GCF=$5\times5\times x=25x$
$-\frac{25x}{75x^2}=-\frac{25x\div25x}{75x^2\div25x}=-\frac{1}{3x}$
