The curves y=x+5 and y=x^{2}-3 x intersect at points A and B. C is a point on the lower curve between A and B. The maximum possible area of the quadrilateral A B C O can be written as \frac{A}{B} for coprime A, B. Find A+B.
The curves y=x+5 and y=x^{2}-3 x intersect at points A and B. C is a point on the lower curve between A and B. The maximum possible area of the quadrilateral A B C O can be written as \frac{A}{B} for coprime A, B. Find A+B.