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Question
If the volume of a cuboid is 3x2 − 27, then its possible dimensions are
Options
3, x2, − 27x
3, x − 3, x + 3
3, x2, 27x
3, 3, 3
Solution
We have to find the possible dimension of cuboid
Given: volume of cuboid `3x^2 - 27`
`3x^2 -27 = 3x^2 - 3xx 3 xx 3`
` = 3x^2 - 3 xx 3 xx 3`
Take 3 as common factor
`3x^2 - 27 = 3(x^2 - 3^2)`
Using identity `x^2 -y^2 = (x+y)(x-y)`
We get,
`3x^2 - 27 =3(3x+3) (x-3)`
Here the dimension of cuboid is 3,3, x + 3, x - 3
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