I'm assuming that the capital and lower case x's are the same
\(x+7x-2=-20\)
You need to get x by itself
Add 2 to each side
\(x+7x-2=-20\) ⇒ \(x+7x=-18\)
Add like variables together
\(8x=-18\)
18÷8=\(2 \frac{2}{8}\) ⇒ \(2 \frac{1}{4}\)
Answer: \(2 \frac{1}{4}\)