Answer:
14 computers
Explanation:
Set the profit, p, equal to $55,000.00 and then solve for x:
-5x^2 + 1000x + 5000 = 55000
Dividing both sides by -5 results in:
x^2 - 200x - 1000 = +11000.
Combining the constant terms results in:
x^2 - 200x - 11000 = 0
Solve this by completing the square:
x^2 - 200x + 10000 - 10000 - 11000 = 0, or
(x - 100)^2 - 21000 = 0, or
(x - 100)^2 = 21000
Taking the square root of both sides, we get
x - 100 = ±10√210, or
x = 100 ± 10√210, or approx. x = 100 + 14.5, or approx 114.5
Sellilng between 114 and 115 computers would result in a profit of $55,000.