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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

 B) $$\Large 5\sqrt{63}$$sq cm

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.

Part of solved Area and perimeter questions and answers : >> Elementary Mathematics >> Area and perimeter

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