#### Answer

0.9p-2000, 0.9p-1800

#### Work Step by Step

Find R(S(p)). This represents the price of the car when the dealership discount is applied before the factory discount.
R(S(p))=R(0.9p)=0.9p-2000
Find S(R(p)). This represents the price of the car when the dealership discount is applied after the factory discount.
S(R(p))=S(p-2000)=0.9p-1800