so the given equation is

m - 4 = 5
We should add 4 on either side as our first step, in order to find the value of the variable

m - 4 ( + 4 ) = 5 ( + 4 )
- 4 and + 4 cancels out in the left hand side
We are left with

m = 9
To find the value of m, we should divide each side by

(diving by a fraction can also be done by multiplying the reciprocal)

m = 9 ÷


cancels out
m = 18