Q = f(P) -> R = (k-mP)P -> kP-mP2
P = f(Q) -> R = Q(k-l/m Q) -> kQ-Q2/m
Misal : Qd=20-2P -> Pd = 10- 1/2Q
Bila P = 3, maka Q = 8
Q=f(P) -> R=20x5-2(3)2 =100-2(9) = 100 -18 = 82
P=f(Q) -> R=10x10-[(8)2/2] =100-64/2=100-32= 68
sumber : putong, iskandar 2010. Ekonomi Pwngantar Mikro dan Makro edisi : 4 jakarta : mitra wacana media