Question

Solve for m. 2= m/2 - 7 whats the answer?

Answer 1

Linear equations are all solved the same way. Figure out the operations performed on the variable. Undo those in reverse order.

Here, the variable is
- divided by 2
- has -7 added.

In reverse order, we undo these operations by
- adding 7
- multiplying by 2.

Whatever we do to one side of an equation, we must also do to the other side. That is how the equal sign remains valid.

2 = m/2 -7
2 +7 = m/2 -7 +7 . . . . . add 7
9 = m/2 . . . . . . . . . . . . simplify
2*9 = 2*m/2 . . . . . . . . multiply by 2
18 = m . . . . . . . . . . . . . simplify. (You know that 2/2 = 1, and m*1 = m.)

The answer is m = 18.

_____
Check:
.. 2 = 18/2 -7
.. 2 = 9 -7 . . . . . . . true. The answer checks OK.