Question

Find the area of a triangle who's side lengths are 13, 14, and 15. (The questions doesn't tell the type of triangle.)

Answer 1

84 square units.

Explanation:

Area of scalene triangle:

`\sf \boxed{\bf Area = √(s*(s-a)(s-b)*(s-c))}`

Here, a, b and c are the sides of the triangle. s is the semi perimeter.

a = 13

b = 14

c = 15

`\sf s= (a+b+c)/(2)\\\\ =(13+14+15)/(2)\\\\=(42)/(2)\\\\s = 21`

s -a = 21 - 13 = 8

s -b = 21 - 14 = 7

s - c = 21 - 15 = 6

`\sf Area = √(21*8*7*6)`

`= √( 7* 3 * 2 * 2 * 2 * 7 * 2 * 3)\\\\=7 * 3 *2*2\\\\= 84 \ square \ units`