Answer:
could it be as simple as x+1=y or y-1=x?
Step-by-step explanation:
y is all of x plus one more.....
He spent 560. Just multiply 70 with 8
Lagrange multipliers:







(if

)

(if

)

(if

)
In the first octant, we assume

, so we can ignore the caveats above. Now,

so that the only critical point in the region of interest is (1, 2, 2), for which we get a maximum value of

.
We also need to check the boundary of the region, i.e. the intersection of

with the three coordinate axes. But in each case, we would end up setting at least one of the variables to 0, which would force

, so the point we found is the only extremum.
The answer to this problem is A 10
I believe its C
Hoped I help :)
And have a nice day/weekend :)
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