Chapter 1 - Equations and Inequalities - Exercise Set 1.2 - Page 118: 21

$x=-15$

First, subtract the fractions. Then multiply the denominator $15$ on both sides. After that multiply $-1$ and $15$ and then you will have the final answer. $-1 = \frac{10x}{15} - \frac{9x}{15}$ $-1 = \frac{x}{15}$ $-1(15) = x$ $x = -15$