(Inverse Demand Equation: = Where P is the price of the product and Q is the quantity demanded )

Your estimate should not be a random number or an arbitrary number. Being the expert for your product, your estimate of the intercept "a", and the slope "b" should make economic sense and be consistent with the nature of your product. You must show the reason(s) why you have chosen a specific value for "a" and "b" because if these estimates are not reasonable, then the demand equation you will construct will be meaningless.

QUESTION: Come up with your best guess/estimate of "a" and "b"

How would I come up with the necessary information to guess/estimate "a" and "b" for a specific product?