Note that

in the given closed interval, so the area is exactly given by the definite integral

(no absolute values needed!)
Integrating gives
The expression foiled together is 6(-3x^2+13xy-4y^2)
Answer:
You paid $40.25 in total.
Step-by-step explanation:
In this question:
Spending of 35%
Tip of 15% means that 15% of 35 will be added to your total spending. So

You paid $40.25 in total.
Call Dawn's wage x, we will have Vesna's wage = x + 17 and Chris' wage = 4x(x + 17). So we have the equation:

Therefore, Chris's wage: