Question
$$12 = 3x-9$$
Answer
$$ x = 7 $$
Explanation
$$ \begin{aligned} 12 &= 3x-9&& \text{ swap the left and right side of the equation } \\[1 em]3x-9 &= 12&& \text{ move -9 to the right } \\[1 em]3x &= 12+9&& \\[1 em]3x &= 21&& \text{ divide both sides by $ 3 $ } \\[1 em]x &= \frac{21}{3}&& \\[1 em]x &= 7&& \\[1 em] \end{aligned} $$
This page was created using
Equations Solver