Question

Check my answer!

Answer 1

$(m - 6)(m + 3)=\\ m^2+3m-6m-18=\\ m^2-3m-18$

Answer 2

M x m  =  m ^ 2
m x 3 =    3m
-6 x m =   -6m
-6 x 3 =    -18

adding these you get    m^2 -3m -18