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 2a + 9a = a - 6z - 9 for a in terms of z.
| -15z - 9 | |
| -1\(\frac{3}{8}\)z + \(\frac{3}{8}\) | |
| -1\(\frac{1}{9}\)z - 1 | |
| -1\(\frac{2}{3}\)z - \(\frac{4}{9}\) |