Simplify $\frac{8x}{12}+\frac{10x}{12}$8x12+10x12

Simplify $\frac{y}{11}-\frac{9y}{11}$y11−9y11

Simplify $\frac{17y}{20}+\frac{14y}{20}$17y20+14y20

Simplify $\frac{7x}{3}-\frac{5x}{3}$7x3−5x3

Multiply a polynomial by a monomial involving the same variable to give results up to degree three using a variety of tools