Distribute (xy + y^{2}) over (2*x* + 9y) to find (xy + y^{2})(2*x*) + (xy + y^{2})(9y) Distribute further to get (xy)(2*x*) + (y^{2})(2*x*) + (xy)(9y) + (y^{2})(9y) and then simplify for 2*x*^{2}y + 2*xy*^{2} + 9*xy*^{2} + 9y^{3} which can be combined further to give us 2*x*^{2}y + 11*xy*^{2} + 9y^{3}. |