Question 84650
(5m-6n+7)(2m-3n-4)

5m(2m-3n-4)-6n(2m-3n-4)+7(2m-3n-4)

10m^2-15mn-20m-12mn+18n^2+24n+14m-21n-28

Simplify

10m^2+18n^2-27mn-6m-3n-28