Question

    What is the value of 8x³ + 18xy + y³ – 27 when 2x +

    y – 3 = 0.
    A –27 Correct Answer Incorrect Answer
    B 27 Correct Answer Incorrect Answer
    D 1 Correct Answer Incorrect Answer

    Solution

    2x + y – 3 = 0 2x + y=3         … (1) Both sides squaring… (2x+y)3 = (3)3 (2x)3+(y)3+3×2x ×y (2x+y) =27 8x3+y3+6xy (3) =27 8x3+y3+18xy =27 8x3+y3+18xy-27 =0.

    Practice Next

    Relevant for Exams: