If mn=5 and m-3n=8, what is m^2n-3mn^2?
\(m^2n-3mn^2=mn(m-3n)=5\cdot 8=40\)
= (m^2)n -3m(n^2). Factorise.=mn( m-3n) : Recall mn = 5. (m-3n) =8.Substituting:=mn( m-3n)= 5*(8) = 40.Cheers.
