• Find the area of a triangle whose sides measure 8 cm, 10 cm and 12 cm.

    A) \( \Large 8\sqrt{63} \)sq cm

      B) \( \Large 5\sqrt{63} \)sq cm

    C) \( \Large 6\sqrt{53} \)sq cm

      D) \( \Large 7\sqrt{93} \)sq cm

    Correct Answer:
      B) \( \Large 5\sqrt{63} \)sq cm

    Description for Correct answer

    Given that,

    a=8cm, b = 10 cm and c=12cm

    We know, that

    s = \( \Large \frac{a+b+c}{2} \) = \( \Large \frac{8+10+12}{2} \)

    = \( \Large \frac{30}{2} \)=15cm

    (s-a)=(15-8)=7cm

    (s-b)=(15-10)=5cm

    (s-c)=(15-12)=3cm

    Area = \(  \Large \sqrt{s(s-a)(s-b)(s-c)} \)

    = \(  \Large \sqrt{15\times 7\times 5\times 3} \)= \(  \Large \sqrt{1575} \)= \(  \Large \sqrt{25\times 63} \)

    = \(  \Large 5\sqrt{63} \)sq cm.


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