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    If (9x - 3y) = 96 and 4x : 3y = 20 : 21, then find the value of (2x² + 3y²).
    Question

    If (9x - 3y) = 96 and 4x : 3y = 20 : 21, then find the value of (2x² + 3y²).

    A.

    2756

    B.

    3341

    C.

    3152

    D.

    2280

    Correct option is C

    Given:
    Equation 1: 9x - 3y = 96
    Equation 2: 4x3y=2021\frac{4x}{3y} = \frac{20}{21}​​
    Solution:
    From the second equation, find the ratio of x to y:
    xy=20×321×4\frac{x}{y} = \frac{20 × 3}{21 × 4}​​
    xy=6084\frac{x}{y} = \frac{60}{84}​​
    xy=57\frac{x}{y} = \frac{5}{7}​​
    Let x = 5k and y = 7k.
    Substitute these into the first equation:
    9(5k) - 3(7k) = 96
    45k - 21k = 96
    24k = 96
    k =9624 \frac{96}{24}​​
    k = 4
    Now find the actual values of x and y:
    x = 5 × 4 = 20
    y = 7 × 4 = 28
    Now calculate the value of 2x2+3y2:2x^2 + 3y^2:​​
    2(20)2+3(28)2 2(20)^2 + 3(28)^2​​
    = 2(400) + 3(784)
    = 800 + 2352
    = 3152
    Final Answer
    So the correct answer is (c)

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