The total area of all the faces of a cuboid is 22 cm2, and the total length of all its edges is 24 cm. Find the length of any one of its internal diagonals.

I can't seem to get this, so any help appreciated

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- Oct 17th 2011, 08:32 AMBobtheBobDiagonal of a Cuboid
The total area of all the faces of a cuboid is 22 cm2, and the total length of all its edges is 24 cm. Find the length of any one of its internal diagonals.

I can't seem to get this, so any help appreciated - Oct 17th 2011, 08:53 AMPlatoRe: Diagonal of a Cuboid
- Oct 17th 2011, 09:42 AMBobtheBobRe: Diagonal of a Cuboid
Ok thanks for the reply. I've already managed to get these equations from the question:

22=2(ab+ac+bc)

24=4(a+b+c)

d= http://latex.codecogs.com/png.latex?...b%5E2+c%5E2%7D.

but I can't manage to work out how to get the lengths? - Oct 17th 2011, 09:55 AMPlatoRe: Diagonal of a Cuboid
- Oct 17th 2011, 10:07 AMBobtheBobRe: Diagonal of a Cuboid
- Oct 17th 2011, 10:16 AMPlatoRe: Diagonal of a Cuboid
- Oct 17th 2011, 10:22 AMBobtheBobRe: Diagonal of a Cuboid
Oh right so ?!

- Oct 17th 2011, 10:25 AMPlatoRe: Diagonal of a Cuboid
- Oct 17th 2011, 10:59 AMBobtheBobRe: Diagonal of a Cuboid
- Oct 17th 2011, 11:07 AMBobtheBobRe: Diagonal of a Cuboid