SOLUTION: P(x)= - 0.08x^2 + 60x - 750 how many units will give a break even point for this product? I'm attempting to use the quadratic equation to solve however I am stuck.

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: P(x)= - 0.08x^2 + 60x - 750 how many units will give a break even point for this product? I'm attempting to use the quadratic equation to solve however I am stuck.      Log On


   



Question 332126: P(x)= - 0.08x^2 + 60x - 750 how many units will give a break even point for this product? I'm attempting to use the quadratic equation to solve however I am stuck.
Found 2 solutions by ankor@dixie-net.com, josmiceli:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
P(x)= - 0.08x^2 + 60x - 750 how many units will give a break even point for this product?
:
Break-even point is when profit is 0, therefore
-.08x^2 + 60x - 750 = 0
using the quadratic formula; x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
in this problem: a=-.08. b=60, c=-750
x+=+%28-60+%2B-+sqrt%2860%5E2-+4+%2A-.08%2A-750+%29%29%2F%282%2A-.08%29+
:
x+=+%28-60+%2B-+sqrt%283600-240+%29%29%2F%28-.16%29+
:
x+=+%28-60+%2B-+sqrt%283360+%29%29%2F%28-.16%29+
Two solutions, but we want the lowest value here
x+=+%28-60+%2B+58%29%2F%28-.16%29+
x = %28-2%29%2F%28-.16%29
x = +12.5, ~ 13 units to break even (a slight profit, integer units required)
;
:
Check in the original equation
-.08(13^2) + 60(13) - 750 = +$43.52, a slight profit

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
If P%28x%29 is
Profit as a function of x units, then the break
even point is where there is zero Profit.
P%28x%29=+-+0.08x%5E2+%2B+60x+-+750
0+=+-+0.08x%5E2+%2B+60x+-+750
Multiply both sides by 100%2F8
0+=+-x%5E2+%2B+750x+-+9375
You can complete the square also
-x%5E2+%2B+750x+=+9375
Multiply both sides by -1
x%5E2+-+750x+=+-+9375
x%5E2+-+750x+%2B+%28750%2F2%29%5E2+=+%28750%2F2%29%5E2+-+9375
x%5E2+-+750x+%2B+375%5E2+=+375%5E2+-+9375
%28x+-+375%29%5E2+=+140625+-+9375
%28x+-+375%29%5E2+=+131250
Take square root of both sides
x+-+375+=+362.284
x+=+737.284
and
x+-+375+=+-362.284
x+=+12.716
There is a break-even point after 12 units and another
after 737 units
Here's a plot: