Question

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The sides of a triangle are 22cm, 20cm and 18 .find the area ​

Answer 1

Answer:

Construct AD.... a perpendicular bisector

Now, refer the image

Answer 2

Answer:

$s = \frac{a + b + c}{2}$

$\: \: \: = ( \frac{ 22 + 20 + 18}{2} ) \: cm$

$\: \: \: = \frac{60}{2} \: cm$

$\: \: \: = 30 \: cm$

$area = \sqrt{s(s - a)(s - b)(s - c) }$

$\: \: \: \: \: \: \: \: \: \: = \sqrt{30(30 - 22} )(30 - 20)(30 - 18) \: {cm}^{2}$

$\: \: \: \: \: \: \: \: \: =\sqrt{30 \times 8 \times 10 \times 12} \: {cm}^{2}$

$\: \: \: \: \: \: \: \: \: \: \: =\sqrt{2×2×2×2×2×2×2×3×3×5×5}$

$\: \: \: \: \: \: \: \: \: = (2×2×2×3×5)\sqrt {2}$

$\: \: \: \: \: \: \: \: \: \: \: = 120 \sqrt {2} \: {cm}^{2}$