Question

during van mahotsav,some children planted trees in a triangular region.two sides of which are 18m and 10m and the perimeter is 42 m.find the are of planted region.

Answer 1

Heya ☺

Given that

Length of 1st side = 18m

Length of 2nd side = 10m

Perimeter = 42m

Length of 3rd side = ?

Solution

Let the length of 3rd side be (x)m. Then,

Perimeter of a triangle = Sum of all sides

=> 42 = 18 + 10 + x

=> 42 = 28 + x

=> 42 - 28 = x

=> 14 = x

Hence , the length of the 3rd side is 14m.

sides = 1/2 (18+14+10)

= 1/2 × 42

= 21m

Area of a triangle

= (21 - 18) (21 - 10) (21 - 14)

= 3 × 11 × 7

= 231m^2

Thanks

Answer 2

The length of the other side of the triangle =(-18+10)m
=(42-28)m
=14m
Now by Euler's formula
s=1/2(18+10+14)
=21
√(s-a)(s-b)(s-c)
√(21-18)(21-10)(21-14)
√3×11×7
√231