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 7a + 8a = -9a + z - 1 for a in terms of z.
| -z - 2 | |
| -\(\frac{7}{16}\)z - \(\frac{1}{16}\) | |
| -\(\frac{1}{9}\)z - \(\frac{2}{3}\) | |
| -\(\frac{5}{13}\)z + \(\frac{9}{13}\) |