Chapter 5.1, Problem 20E

In Exercises 17–22, a price ceiling or price floor is given along with demand and supply functions, where D(x) is the price, in dollars per unit, that consumers will pay for $x$ units, and S(x) is the price, in dollars per unit, at which producers will sell $x$ units. Find (a) the equilibrium point, (b) the point $(x_C,p_C\text{) }or\text{ (}{x}_F,p_F)$, (c) the new consumer surplus, (d) the new producer surplus, and (e) the deadweight loss.

20. $D\left(x\right)=\text{1}25-2.25x,S\left(x\right)=20+\text{1}.5x,P_F=\$90$