The total cost and total revenue function of a commodity are given by C(x) =x+40 and $R(x) =ax-bx^2$.Break-even points are 5, 40 then a and b are :

$a=10, b=0.2$

The correct answer is Option (2) → $a=10, b=0.2$

The Break events point occurs,

$C(x)=R(x)$

when $x=5$,

$5+40=a(5)-b(5)^2$

$45=5a-25b$   ...(1)

when $x=40$,

$40+40=a(40)-b(40)^2$

$40a-1600b=80$    ...(2)

from (1) and (2) we get,

$b=\frac{1}{5},a=10$