Answer:
Without an equivalence given (i.e. an equals sign somewhere in the expression), we have no way of solving for m.
We can however simplify it:
m²(2 - 3m) - 6m(1 - 4m + 5m²)
= 2m² + 3m³- 6m + 24m² - 30m⁴
= 26m² + 3m³ - 6m - 30m⁴
= m(-30m³ + 3m² + 26m - 6)