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The side length, s, of a cube is 3x + 2y. If V = s3, what is the volume of the cube?

User Shaoyihe
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2 Answers

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We are given side of the cube (s) = (3x+2y).

Also, formula for Volume of the cube is
V=s^3.

Substituting s=(3x+2y) in formula of volume of the cube written above, we get


V =(3x+2y)^3


\mathrm{Apply\:Perfect\:Cube\:Formula}:\quad \left(a+b\right)^3=a^3+3a^2b+3ab^2+b^3


a=3x,\:\:b=2y


=\left(3x\right)^3+3\left(3x\right)^2\cdot \:2y+3\cdot \:3x\left(2y\right)^2+\left(2y\right)^3


\left(3x\right)^3+3\left(3x\right)^2\cdot \:2y+3\cdot \:3x\left(2y\right)^2+\left(2y\right)^3:\quad 27x^3+54x^2y+36xy^2+8y^3


=27x^3+54x^2y+36xy^2+8y^3

Therefore, volume of the cube is
V=27x^3+54x^2y+36xy^2+8y^3. units cube.


User Rgomesf
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7 votes
Answer:
volume = 27x^3 + 54x^y + 36xy^2 + 8y^3

Step-by-step explanation:
The volume of the cube is calculated using the following rule:
volume = s^3

We are given that the side length of the cube = s = 3x+2y

Substituting in the equation we can get the volume as follows:
volume = (3x+2y)^3
volume = (3x+2y)^2 * (3x+2y)
volume = (9x^2 + 12xy + 4y^2)*(3x+2y)
volume = 27x^3 + 36x^2y + 12xy^2 + 18x^2y + 24xy^2 + 8y^3
volume = 27x^3 + 54x^y + 36xy^2 + 8y^3

Hope this helps :)
User Addedlovely
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