Answer:
solution is

Step-by-step explanation:
We are given equation as

Firstly, we will find equations
First equation is

Second equation is

now, we can draw graph
and then we can find intersection point
we can see that
intersection point is (1.353,1.613)
so, solution is

I believe you are correct
Its 90 because its a L shaped will means its 90
It is a linear graph that goes down $1500 every hint so at 8 hints the contestant will win $0.