Does anyone know how to solve this?

m = -1

Step-by-step explanation:

-13 - 5m = -4 + 4m

First you want to get the m's on the same side, and remember, what you do to one side you do to the other.

-13 -5m + 5m = -4 + 4m +5m

-13 = -4 + 9m

Now, isolate the m

-13 + 4 = -4 + 9m + 4

-9 = 9m

-9/9 = 9m/9

-1 = m

Check

-13 - 5(-1) = -4 + 4(-1)

-13 + 5 = -4 - 4

-8 = -8

Hope this explains it!