Math
posted by Nancy .
a) f(x) = 4.1x +92.16
b) f(x) = 17.9x + 19.36
c) f(x) = 8.8x + 55.4
ANSWERS: a) 4.8 b) 0.93 c) 2.2, i just have no clue how they got these answers
EXTRA INFO:
The demand function for a new product is p(x)=  4x +42.5, where x is the quantity sold in thousands and p is the price in dollars. the company that manufactures the product is planning to buy a new machine for the plant. there are 3 diff. types of machines. the cost function for each machine is shown (ABOVE). Investigate the break even quantities for each machine.

If the demand is met, the total revenue is price per unit * number of units
for machine (a)
revenue = p(x)*x = 42.5x  4x^2
cost = f(x)*x = 4.1x^2 + 92.16
breakeven is where cost = revenue
42.5x  4x^2 = 4.1x + 92.16
4x^2 38.4x + 92.16 = 0
x^2  9.6x + 23.04 = 0
x = 4.8
So, for unit (a) the breakeven occurs at 4800 units
Go forth and do likewise for (b) and (c) 
typo: f(x) = 4.1x + 92.16, not 4.1x^2