Mrs. Shaw writes this equation on the board. She asks the students to find
the solution.
-40 -2(3m + 1/2)= 7m -2
Keith’s work is shown below. What mistake did Keith make?
-40 - 6m + 1 = 7m - 2
-39 - 6m = 7m -2
-39 = 13m - 2
-37 = 13m
-2 11/13 = m