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 - 9a = -3a - 7y + 9 for a in terms of y.
| 1\(\frac{1}{2}\)y - 2 | |
| \(\frac{1}{4}\)y - 2\(\frac{1}{4}\) | |
| \(\frac{1}{5}\)y + \(\frac{9}{10}\) | |
| -\(\frac{5}{6}\)y + \(\frac{2}{3}\) |