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 + 3a = 8a + 2z - 4 for a in terms of z.
| -z - 4 | |
| -\(\frac{1}{2}\)z - 4\(\frac{1}{2}\) | |
| -\(\frac{1}{8}\)z + 1 | |
| \(\frac{2}{7}\)z + \(\frac{5}{14}\) |