Question

david makes and sells chairs. The function p(x)=-10x^2+100x-210, graphed below, indicated how much profit he makes in a month if he sells the chairs for 9-x dollars each. what should david charge per chair to make the maximum profit, and what is the maximum profit he can make in a month? (one sec while I post the graph)

Answer 1

If anyone can work this out for me I would love it. I am very behind in math and am timed to get it done :<

Answer 2

p(x) = -10x^2 + 100x - 210,
p(9 - x)
= -10(9 - x)^2 + 100(9 - x) - 210
= -10x^2 + 80x - 120
= -10(x - 2)(x - 6)
x = 2, x = 6
Answer choice:
B) $50 at $7 per chair