Question

(m-4) (m+9)-5m(1-2m)

Answer 1

(m-4) (m+9)-5m(1-2m)=m²-4m+9m-5m+10m²=11m²

Answer 2

(m-4)(m+9)-5m(1-2m)=$m^{2} +9m-4m-36-5m+10m^2= \\ \\ =11m^2-36$