Mohon cepat yang fungsi konsumsi

Y1 = 5000
S1 = 300
Y2 = 7000
S2 = 1000

C1 = Y1 - S1
C1 = 5000 - 300
C1 = 4700

C2 = Y2 - S2
C2 = 7000 - 1000
C2 = 6000

Fungsi konsumsi:
(C - C1)/(C2 - C1) = (Y - Y1)/(Y2 - Y1)
(C - 4700)/(6000 - 4700) = (Y - 5000)/(7000 - 5000)
(C - 4700)/1300 = (Y - 5000)/2000 (Kali 100 kedua ruas)
(C - 4700)/13 = (Y - 5000)/20
20(C - 4700) = 13(Y - 5000)
20C - 94000 = 13Y - 65000
20C = 13Y - 65000 + 94000
20C = 13Y + 29000 (bagi 20 kedua ruas)
C = 0,65Y + 1450
C = 1450 + 0,65Y

Jawaban: D atau E