[tex]\dfrac{5}{2}(4m-8)- 2(6m -7)= -10\\\\\\\dfrac{5\cdot4}{2}m-\dfrac{5\cdot8}{2}- 2\cdot6m -2\cdot(-7)= -10\\\\\\\dfrac{20}{2}m-\dfrac{40}{2}-12m+14=-10\\\\\\10m-20-12m+14=-10\\\\-2m-6=-10\quad|\cdot(-1)\\\\2m+6=10\\\\2m=10-6\\\\2m=4\quad|:2\\\\\boxed{m=2}[/tex]
Answer C.
