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Question

I am working on this problem and I’m having trouble figuring out how to solve it.please help.

It’s a quadratic word problem. The demand equation for a certain product is given by P equals 140-0.075x, where P is the unit price (in dollars) of the product and X is the number of units produced. The total revenue obtained by producing and selling X units is given by R equals XP. Determine the price is P that would yield a revenue of 9870 dollars lowest price equals___________dollars. Highest price _________ dollars.

Answer 1

p=140-.075x

px=9870=140x-.075x^2

.075x^2 -140x +9870=0

either use the quadratic formula

or use a graphing calculator and see where the curve intersects the x axis

x= 140/.15 +/-(1/.15)sqr(140^2 -4(.075)(9870))

x= 73.385

p=140-.075(73.385)

or

x=1793.282

p=140-.075(1793.282)