When solving an equation with two variables, replace the variables with the values given and then solve the now variable-free equation. (Remember order of operations, PEMDAS, Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.)
Solve -a + 8a = -2a + z - 7 for a in terms of z.
| -7z - 7 | |
| \(\frac{1}{13}\)z - \(\frac{2}{13}\) | |
| 1\(\frac{1}{2}\)z - 4\(\frac{1}{2}\) | |
| -15z - 6 |