Answer:
m = - 2
Explanation:
The terms between consecutive terms have a common difference, that is
a₂ - a₁ = a₃ - a₂ ( substitute values )
6m - 2 - (8m + 1) = 2m - 9 - (6m - 2) ← distribute parenthesis on both sides
6m - 2 - 8m - 1 = 2m - 9 - 6m + 2 , that is
- 2m - 3 = - 4m - 7 ( add 4m to both sides )
2m - 3 = - 7 ( add 3 to both sides )
2m = - 4 ( divide both sides by 2 )
m = - 2