$$10\cdot(1+3x) = -20$$
Answer
$$ x = -1 $$
Explanation
$$ \begin{aligned} 10\cdot(1+3x) &= -20&& \text{simplify left side} \\[1 em]10+30x &= -20&& \\[1 em]30x+10 &= -20&& \text{ move 10 to the right } \\[1 em]30x &= -20-10&& \\[1 em]30x &= -30&& \text{ divide both sides by $ 30 $ } \\[1 em]x &= -\frac{30}{30}&& \\[1 em]x &= -1&& \\[1 em] \end{aligned} $$
This page was created using
Equations Solver