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 -3a - a = 8a + 9z - 9 for a in terms of z.
| -1\(\frac{1}{5}\)z + 1\(\frac{4}{5}\) | |
| -\(\frac{10}{11}\)z + \(\frac{9}{11}\) | |
| -5z - 2\(\frac{1}{2}\) | |
| -\(\frac{5}{7}\)z + 1\(\frac{1}{7}\) |