Find Unknown Variables a, b, c in V=abc Equation | Volume 512cm^3

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AI Thread Summary
The volume equation V = abc is given with V = 512 cm^3, where a = 2b and b = 2c. By substituting these relationships into the volume equation, it simplifies to V = 8c^3. Solving for c yields c = 4 cm, which allows for the calculation of b and a as b = 8 cm and a = 16 cm, respectively. The final verification confirms that V = 16 cm * 8 cm * 4 cm equals 512 cm^3, validating the solution. The calculations and relationships between the variables are correctly established.
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Homework Statement


The volume is 512cm^3. Known as V=abc; a = 2b, b = 2c. Find a, b, c


Homework Equations


V = 512cm^3.
a = 2b
b = 2c


The Attempt at a Solution


V=2b * 2c * c
V=2b * 2c^2
512cm^3=2b * 2c^2
 
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besfort said:
512cm^3=2b * 2c^2

You know the relation between b and c, so you can write this expression in terms of 1 variable.
 
So this would be written as 2 * 2c * 2c^2 which would result to 8c^3, right?
 
besfort said:
So this would be written as 2 * 2c * 2c^2 which would result to 8c^3, right?

Yes :-)
 
I came to the result where V=8c^3 and c = 4 cm. Then b was found from the equation of 2c, and a was found by the equation of 2b.

I came to the result;
a = 16cm,
b = 8cm,
c = 4cm

V = 16cm * 8cm * 4cm
V = 512 cm^3

Which is correct. Thank you for the help!
 
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