Thread: Demand curve

May i know how to form quadratic equation for demand curve?
Data is shown below :
Unit Price (P) in $ Quantity Demanded (Q) in units
P Q
0 500
5 450
8 372
10 300
12 212
15 50

Hey jiawen921212.

Do you have to fit the curve through all the points or just find the best fit?

Also have you heard of least squares fitting?