New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    If (a + b) = 7 and ab = 10, then find the value of (a

    2  + b 2 ).
    A 19 Correct Answer Incorrect Answer
    B 29 Correct Answer Incorrect Answer
    C 9 Correct Answer Incorrect Answer
    D 39 Correct Answer Incorrect Answer

    Solution

    According to the question,

    (a + b) 2  = 7 2

    Or, a 2  + b 2  + 2ab = 49

    Or, a 2  + b 2  + 20 = 49

    So, a 2  + b 2  = 49 - 20 = 29

    Practice Next