Answer:
4 years
Step-by-step explanation:
Look for the year where the green bar is higher than the red bar.
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.
Area of base
So possible dimensions are optionB given
Verified
The coefficient of X is -2
Answer:
the slope of the line is <u>4</u><u> </u><u>and</u><u> </u><u>the</u><u> </u><u>working</u><u> </u><u>is</u><u> </u>in the attached picture