
William W. answered 05/20/20
Top Algebra Tutor
If you are trying to make the total sales and total cost equal to each other then you make S(x) = C(x) or:
-200x2 + 70000x = -22000x + 8375000
This is a quadratic equation and the way we typically solve quadratics is to set them equal to zero. So, let's move the terms on the right over to the left by adding 22000x and subtracting 8375000 from both sides:
-200x2 + 92000x - 8375000 = 0 [now divide both sides by -200
x2 - 460x + 41875 = 0 [now factor it or use the quadratic formula. I'll factor:
(x - 125)(x - 335) = 0
Then set each piece equal to zero to find x:
x - 125 = 0 or x = 125
x - 335 = 0 or x = 335
These 2 prices ($125 and $335) will make the sales and cost equal. The value of the cost for each is:
C(125) = $5,625,000
C(335) = $1,005,000