Question

✓15+(15-8)(15-12)(15-10)

Answer 1

I hope you are trying to find out the area of triangle whose semi-Perimeter is 15.

But it's formula is..
$= > \sqrt{s(s - a)(s - b)(s - c)} \\ \\ where \: \: \: s = \frac{a + b + c}{2} = semi - perimeter \\ \\ and \: \: a \: ...b...c \: \: are \: the \: sides$
So.. Using this formula,

Required Area of the triangle is

$= \sqrt{15(15 - 8)(15 - 12)(15 - 10)} \\ \\ = \sqrt{15 \times 7 \times 3 \times 5} \\ \\ = 15 \sqrt{7 } \: \: or \: \: 39.63 \: \: sq \: \: units$
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Hope this is ur required answer

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