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    The difference between the squares of two numbers is 39 and the sum of these two numbers is 13. What are those numbers?
    Question

    The difference between the squares of two numbers is 39 and the sum of these two numbers is 13. What are those numbers?

    A.

    4, 3

    B.

    10, 3

    C.

    8, 5

    D.

    7, 6

    Correct option is C

    Given:

    The difference between the squares of two numbers = 39

    The sum of these two numbers = 13

    Formula Used:

    a2b2=(a+b)(ab)a^2 - b^2 = (a + b)(a - b)​​

    Solution:

    Let the two numbers be a and b.

    Given a2b2^2 - b^2 ​= 39 and a + b = 13:

    a2b2=(a+b)(ab)a^2 - b^2 = (a + b)(a - b)​​

    39 = 13 × (a - b)

    ab=3913=3a - b = \frac{39}{13} = 3​​

    a - b = 3  , a + b = 13

    Adding these two equations:

    (a + b) + (a - b) = 13 + 3

    2a = 16

    a = 8

    Substituting a = 8 into a + b = 13:

    8 + b = 13

    b = 5

    The two numbers are 8 and 5.

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