3m-5n = jesli m=-4/7 , n=4/3
3m-5n=3*(-4/7)-5*(+4/3)=-12/7-(+20/3)=-12/7 - 20/3=
=(-36-140)/21 = - 176/21
3m-5n = jesli m=-4/7 , n=4/3
3m-5n=3*(-4/7)-5*(+4/3)=-12/7-(+20/3)=-12/7 - 20/3=
=(-36-140)/21 = - 176/21