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 -6a - 3a = a + 9z + 9 for a in terms of z.
| -2z + \(\frac{1}{4}\) | |
| \(\frac{5}{14}\)z - \(\frac{3}{14}\) | |
| \(\frac{4}{7}\)z - 1 | |
| -1\(\frac{5}{7}\)z - 1\(\frac{2}{7}\) |