Question

find the area of triangle of sides 15cm, 12cm and 20cm​

Answer 1

Answer:

Area of the triangle = 89.28 cm²

Step-by-step explanation:

Given :

Side of the triangle = 15 cm , 12 cm , 20 cm

To find :

The area of the triangle

Taken :

First find the semi perimeter of the triangle . To find the semi - perimeter use this formula -:

$\boxed{\bf{s=\dfrac{a+b+c}{2}}}$

Where,

s = Semi - Perimeter

a = First side

b = second side

c = Third side

After that to find the area of the triangle use this formula -:

$\boxed{\bf{A=\sqrt{s(s-a)(s-b)(s-c)}{cm}^{2}}}$

Solution :

Semi-perimeter -:

$:\implies\bf{s=\dfrac{15cm+12cm+20cm}{2}}$

$:\implies\bf{s=\dfrac{\cancel{47cm}}{\cancel{2}}}$

$:\implies\bf{s=23.5cm}$

Area of the triangle -:

$:\implies\bf{A=\sqrt{23.5(23.5-15)(23.5-12)(23.5-20)}{cm}^{2}}$

$:\implies\bf{A=\sqrt{23.5\times8.5\times11.5\times3.5}{cm}^{2}}$

$:\implies\bf{A=4.84\times2.91\times3.39\times1.87\:\:{cm}^{2}}$

$:\implies\bf{A=89.28{cm}^{2}(approx) }$

So , the area of the triangle is 89.28 cm² (approx) .

Answer 2

Answer:

I hope that it will help you