SOLUTION: A can sell 20 books per day at Rs 25 per book but he can sell 30 books if he charges Rs 20 per book. Determine the demand function assuming it linear

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Question 920424: A can sell 20 books per day at Rs 25 per book but he can sell 30 books if he charges Rs 20 per book. Determine the demand function assuming it linear
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!

(30, 20)
(20, 25 ) m =%28y%5B1%5D+-+y%5B2%5D%29%2F%28x%5B1%5D+-+x%5B2%5D+%29= -5/10 = -2
***Using point-slope form, y+-+y%5B1%5D+=+m%28x+-+x%5B1%5D%29 P(20,25)
y - 25 = -2(x-20)
y = -2x +65
p(x) = -2x + 65 is the Demand Function