Let x = one of the side lengths of the base.
Then area of the base = x². So volume of the base = x²h.
That gives us x²h = 20. Solving for x, we get x = √(20/h²).
Glass is needed to cover the sides of the aquarium. There are 4 sides and 1 base. Area of a side = hx = h√(20/h²). Area of the base = x² = 20/h. Total area of glass = h√(20/h²) + 20/h. So the cost for glass = 8 * [h√(20/h²) + 20/h] = 8 h√(20/h²) + 160/h.
Metal frame is needed along the edges of the sides. There are 4 edges on the top, 4 edges in the bottom and 4 vertical edges. So the total length of metal frame = 4x + 4x + 4h = 8 √(20/h²) + 4h. Then the cost for metal frame = 7 * [8 √(20/h²) + 4h] = 56 √(20/h²) + 28h.
So the total cost = 8 h√(20/h²) + 160/h + 56 √(20/h²) + 28h
Xy = 216
x = 216/y
2x + 2y = 60
2(216/y) + 2y = 60
432 + 2y^2 = 60y
2y^2 - 60y + 432 = 0
y = 18 , y = 12
if y = 12
x = 216/12
x = 18
length = 18
width = 12
Answer:
1385
Step-by-step explanation:
1) the difference is d=25-8=42-25=17;
the sequence given in the condition is arithmetic one (linear relationship).
2) in order to calculate the value of the 82d term:
a(n)=a(1)+d*(n-1), where n - number of required term (it is 82), then
a(82)=8+17*(82-1)=8+1377=1385.
