Answer: 
Step-by-step explanation:

Add
on both sides and subtract
on both sides to leave x's on the left side and independent values on the right.


Solve the fractions.





Convert the mixed fraction
to an improper fraction. You can do this by multiplying 1 times 35 and adding 2.

Now use the reciprocal (inverse fraction) and multiply on both sides to isolate x.




Hold on i believe its C but let me go look on google and i'll get back to you to sure
Answer:
For least material to be used lengths of square base and sides = 10 units.
Step-by-step explanation:
Let the lengths of the square base and the sides = x feet, x feet and y feet
Area of the square base = x² feet
Volume of the rectangular prism = Area of the square base × Height
= x²y cubic feet
1000 = x²y
y =
-------(1)
Material used in the prism = Surface area of the rectangular prism
= 2(lb + bh + hl)
Here, h = height of the prism
l = length of the base
w = Width of the base
Material to be used (S) = 2(xy + x² + xy) - Area of lid
S = 2(x² + 2xy) - x²
S = x² + 2xy
Now by substituting the value of y from equation (1),
S = x² + 
= x² + 
For least amount of material used,
We will find the derivative of the given function and equate it to zero.
S' = 2x - 
2x -
= 0
2x³ = 2000
x³ = 1000
x = 10 feet
From equation (1),
y = 
y = 10 feet
Therefore, for least amount of the material used lengths of square base and sides will be 10 feet.