Variable $x$ cannot be equal to $0$ since division by zero is not defined. Multiply both sides of the equation by $3x$, the least common multiple of $3,x$.
$$-10x=3\times 5$$
Multiply $3$ and $5$ to get $15$.
$$-10x=15$$
Divide both sides by $-10$.
$$x=\frac{15}{-10}$$
Reduce the fraction $\frac{15}{-10}$ to lowest terms by extracting and canceling out $5$.
