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The formula s = StartRoot StartFraction S A Over 6 EndFraction EndRoot gives the length of the side, s, of a cube with a surface area, SA. How much longer is the side of a cube with a surface area of 1,200 square inches than a cube with the surface area of 768 square inches?

2 Answers

3 votes

Answer:

Its B

Explanation:

Edge 2021

User McAden
by
5.6k points
1 vote

Answer:


2√(2)\ ft\ longer

Explanation:

Area Of A Cube

Suppose a cube with side length s, the area of one side is


A_s=s^2

Since the cube has 6 sides, the total area is


A=6A_s=6s^2

But if we have the area, we can solve the above formula for s to get


A=6s^2


\displaystyle s=\sqrt{(A)/(6)}

We have two different cubes with areas 1,200 square inches and 768 square inches. Let's compute their side lengths


\displaystyle s_1=\sqrt{(1,200)/(6)}=√(200)


\displaystyle s_1=10√(2)\ ft


\displaystyle s_2=\sqrt{(768)/(6)}=√(128)


\displaystyle s_2=8√(2) ft

The difference between them is


10√(2)\ ft-8√(2)\ ft=2√(2)\ ft\approx 2.83\ ft

The side of the cube with area 1,200 square inches is
2√(2)\ ft longer then the side of the cube with area 768 square inches

User Siarhei Fedartsou
by
5.7k points