98 = m- -78
Thank you

98 = m - -78

First, simplify m - -78 to m + 78. / Your problem should look like: 98 = m + 78.
Second, subtract 78 from both sides. / Your problem should look like: 98 - 78 = m.
Third, simplify 98 - 78 to 20. / Your problem should look like: 20 = m.
Fourth, switch sides. / Your problem should look like: m = 20.

 m = 20