Answer:
49.5 mi
Step-by-step explanation:
Area of a triangle is A = (height) X (base) / 2
So if you plug in the numbers you get:
806.9 = (32.6) X (base) / 2
1613.8 = (32.6) X (base)
1613.8 / 32.6 = base
base = 49.5 mi
14 is 10% of 140 because u do 14÷10% and u get 140
X = shorter piece
y = longer piece = 5x
shorter piece + longer piece = 60
x + 5x = 60
6x = 60
x = 60/6
x = 10 in. <== shorter piece
y = 5x
y = 5(10)
y = 50 in. <== longer piece
The amount of water that is needed to fill the pool is equal to the volume of the pool.
The pool is rectangular, with uniform depth so the volume of pool will be the product of its length , width and depth.
Thus,
Volume = 25 x 18 x 6 = 2700 ft³
This means, 2700 ft³ water is needed to fill the pool.
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.