Hope you can see the picture and understand the drawings.
It can seem complex at first but you just have to think it through.
I use pythagoras' theorem to find the diagonal of the base square and then use that information along with the height with the aid of that ever so handy pythagoras' theorem to find the length of the slope.
512 is the coefficient of the x9y-term
Find the volume of the first figure, then find the volume of the second figure, then add them together.
V=lwh
V(1)=(15)(12)(6)
= 1,080in^3
V(2)=(12)(6)(6)
= 432in^3
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1,080+432= 1,512 in^3
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Your answer should be 1,512
Only 4,52 would be on the graph.
If she stated at week 0 with 32 dollars it would be:
0, 32
1, 37
2, 42
3, 47
4, 52
5, 57
6, 62
7, 67
and so on.