Question

    If the sum of a number and its square is 156, then what

    is the number?
    A 14 Correct Answer Incorrect Answer
    B 12 Correct Answer Incorrect Answer
    C 11 Correct Answer Incorrect Answer
    D 13 Correct Answer Incorrect Answer

    Solution

    According to the question, x + x2 = 156 ⇒ x2 + x - 156 = 0 ⇒ x2 + 13x - 12x - 156 = 0 ⇒ x(x + 13) - 12(x + 13) = 0 ⇒ (x + 13)(x - 12) = 0 ∴ x = -13, 12 ∴ The positive number is 12.

    Practice Next

    Relevant for Exams: