Answer:

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Step-by-step explanation:
We're tasked to find the values of a,b,c,d in the following

The equation of the line through the points (0,15) and (5,0) is y = -3x+15
When picking a particular fixed x value, the y values span from y = 0 to y = -3x+15 which determines the bounds of integration for the inner integral.
So this means c = 0 and d = -3x+15
The values of a,b are much easier and they are a = 0 and b = 5 to represent the x coordinates of the left-most and right-most points.
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Since,
- a = 0
- b = 5
- c = 0
- d = -3x+15
we go from this

to this

Without knowing what f(x,y) is, we cannot compute the integral. Luckily it seems like your teacher is only interested in setting up the integral rather than computing its numeric value.