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    If (x + iy)(2 - 3i) = 4 - i, find the real values of x and y.
    Question

    If (x + iy)(2 - 3i) = 4 - i, find the real values of x and y.

    A.

    x=1413,y=513x = \frac{14}{13}, y = \frac{5}{13}

    B.

    x=513,y=1413x = \frac{5}{13}, y = \frac{14}{13}

    C.

    x=213,y=1x = \frac{2}{13}, y = 1

    D.

    x=1113,y=1013x = \frac{11}{13}, y = \frac{10}{13}

    Correct option is D

    Solution:

    1. Expand the expression:
    (x+iy)(23i)=2x3xi+2iy3iy2(x + iy)(2 - 3i) = 2x - 3xi + 2iy - 3iy^2
    Since i2i^2​ = -1, this simplifies to:
    2x - 3xi + 2iy + 3y
    Rearrange into real and imaginary parts:
    (2x + 3y) + (-3x + 2y)i

    2. Equate to the given value 4 – i :
    (2x + 3y) + (-3x + 2y)i = 4 - i
    Equating real and imaginary parts:
    2x+3y=4(1)2x + 3y = 4 \tag{1}
    3x+2y=1(2)-3x + 2y = -1 \tag{2}

    3. Solve the system of equations:
    From equation (1):
    x=43y2(3)x = \frac{4 - 3y}{2} \tag{3}
    Substitute equation (3) into equation (2):
    3(43y2)+2y=1-3\left(\frac{4 - 3y}{2}\right) + 2y = -1
    Simplify:
    129y2+2y=1-\frac{12 - 9y}{2} + 2y = -1
    Multiply through by 2 to eliminate the fraction:
    -12 + 9y + 4y = -2
    Combine terms:
    13y=10=>y=101313y = 10 \quad \Rightarrow \quad y = \frac{10}{13}

    4. Substitute y = 1013\frac{10}{13}​ into equation (3):
    x=43(1013)2x = \frac{4 - 3\left(\frac{10}{13}\right)}{2}
    Simplify:
    x=430132=521330132=22132=1113x = \frac{4 - \frac{30}{13}}{2} = \frac{\frac{52}{13} - \frac{30}{13}}{2} = \frac{\frac{22}{13}}{2} = \frac{11}{13}

    Final Answer:

    The values are:
    x=1113,y=1013x = \frac{11}{13}, \quad y = \frac{10}{13}
    Correct Option: **(D)**

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