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    The volume of a cuboid is 5a2 - 80b2. Which of the options below can be possible dimensions of the cuboid?
    Question

    The volume of a cuboid is 5a2 - 80b2. Which of the options below can be possible dimensions of the cuboid?

    A.

    5, 2a-b, 2a+b

    B.

    5, a-4b, a+4b

    C.

    5, a-b, a+4b

    D.

    5, 2a-b, a+2b

    Correct option is B

    Given :

    The volume of the cuboid(V) = 5a2^2-80b2^2 

    Formula Used: 

    ​The volume of the cuboid;

    V = Length × Breadth × Height  

    Solution: 

    Analyzing the each option :

    Option (a): 5 , 2a−b , 2a+b

    The volume would be:

    V=5 × ( 2a − b ) × ( 2a + b )

    V = 5 × ( 4a2^2 − b2^2 ) = 20a2^2 − 5b2^2

    So, option (a) is not correct.

    Option (b): 5 , a−4b , a + 4b

    The volume would be:

    V = 5 × ( a − 4b ) × ( a + 4b )

    V = 5 × ( a2^2 − 16b2^2 ) = 5a2^2 − 80b2^2

    This is equal to 5a280b25a^2 - 80b^2

    So, option (b) is correct

    Option (c): 5 , a−b , a+4b

    V=5 × ( a − b ) × ( a + 4b )

    V=5×(a2+3ab4b2)V = 5 \times (a^2 + 3ab - 4b^2)​​

    So option (c) is not correct.

    Option (d): 5 , 2a−b , a+2b

    The volume would be:

    V = 5 × ( 2a − b ) × ( a + 2b )

    V = 5 × ( 2a2^2 + 3ab − 2b2^2 ) =10a2^2​+15ab − 10b2^2

    So option (d) is not correct.

    The, possible dimensions of the cuboid : 5 , a−4b , a + 4b

    Hence, Option (b) is correct answer

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