📢 Too many exams? Don’t know which one suits you best? Book Your Free Expert 👉 call Now!


    Question

    What is the inradius of a right-angled triangle if its base

    measures 20 cm and its height (perpendicular) is 21 cm?
    A 12 cm Correct Answer Incorrect Answer
    B 8 cm Correct Answer Incorrect Answer
    C 10 cm Correct Answer Incorrect Answer
    D 6 cm Correct Answer Incorrect Answer

    Solution

    By Pythagoras theorem,

    Hypotenuse 2  = base 2  + perpendicular 2

    Hypotenuse 2  = 20 2  + 21 2

    Hypotenuse 2  = 400 + 441 = 841

    So, hypotenuse = 29 or – 29

    But hypotenuse cannot be negative. So, hypotenuse = 29 cm

    Inradius of a right-angled triangle = (Perpendicular + Base – Hypotenuse) ÷ 2 = (21 + 20 – 29) ÷ 2 = 6 cm

    Practice Next
    ask-question

    Not sure which exam is best for you Talk to our expert

    Get My Free Call