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 -9a - a = -7a - 8z - 7 for a in terms of z.
| -3z - 4\(\frac{1}{2}\) | |
| -\(\frac{1}{7}\)z + \(\frac{3}{7}\) | |
| z + \(\frac{6}{11}\) | |
| 3\(\frac{1}{2}\)z + 3\(\frac{1}{2}\) |