Find the area of the triangle whose sides are 8cm, 6cm and 4cm.

1.	Find the area of the triangle whose sides are 8cm, 6cm and 4cm.
Answer» {tex}\\text {Area of triangle with all three sides known, can be found by Heron\'s Formula.}{/tex}{tex}\\text {Area} = \\sqrt {s(s-a)(s-b)(s-c}{/tex}{tex}\\text {where, }a, b \\text { and } c \\text { are sides of triangle, and }s \\text { is the semi-perimeter of triangle.}{/tex}{tex}Here, a=8\\text { cm}, b=6 \\text { cm and }c=4 \\text { cm.}{/tex}{tex}\\therefore s=\\cfrac {a+b+c}{2}=\\cfrac {8+6+4}{2} = \\cfrac {18}{2} = 9 \\text { cm.}{/tex}{tex}\\text {Area =} \\sqrt {9(9-8)(9-6)(9-4)}{/tex}{tex}\\Rightarrow \\text {Area = } \\sqrt {9(1)(3)(5)}= 3 \\sqrt {15} \\text { sq. units Ans.}{/tex}

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