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