I'm guessing you needed this factored and apologies for the lateness, this popped up after I answered another question.
12m³ - 22m² - 70m
2m(6m² - 11m - 35)
2m(6m² + 10m - 21m - 35)
2m(2m(3m + 5) - 7(3m + 5))
Your factored answer is:
2m(2m - 7)(3m + 5)
