Rolf K. answered 05/07/20
Med School Prof for Science, Statistics, SAT, MCAT, DAT & GRE
Breakeven point: c = p
1.025 x2 - 4 x + 20 = 2.125 x2 + 6 x + 40 Rewrite by adding the left side to the right of the equation:
1.1 x2 + 10 x + 20 = 0 Rewrite with 10 as the denominator:
(11 x2 + 100 x + 200)/10 = 0 Multiply both sides by 10:
11 x2 + 100 x + 200 = 0 Trinomial cannot be factored, therefore use quadratic formula:
Quadratic Formula:
Ax2 + Bx + C = 0, where A, B and C are coefficients, is given by :
- B ± √ B2 - 4 AC
x = ————————; this equation has two solutions:
2 A
- 100 ± √ 10,000 - 4*11*200 - 100 ± 100 - 8,800 - 8,800
x = —————————————— = ————————— = ————— = - 400
2*11 22 22
-8,800 9,000
x1 = ————— = - 400; x2 = ————— = + 409.1
22 22
Because cost is not negative, the answer is in x2 = 409.1.