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.)
If b = 3 and z = 1, what is the value of 7b(b - z)?
| 12 | |
| 42 | |
| 72 | |
| -90 |