Question

Find the area of a triangle with legs that are: 9 mm, 6 mm, and 12 mm.

A. 26.1 mm
B. 12.3 mm
C. 11.6 mm
D. 37 mm?

Answer 1

Explanation:

a = 9 mm ; b = 6 mm ; c = 12 mm

S = (a + b +c) / 2

`= (9 + 6 + 12)/(2)\\\\= (27)/(2)\\\\= 13.5 \ mm`

S - a = 13.5 - 9 = 4.5 mm

s -b = 13.5 - 6 = 7.5 mm

s -c = 13.5 - 12 = 1.5 mm

Area =
`√(s(s-a)(s-b)(s-c))`

`= √(13.5 * 4.5 * 7.5 * 1.5) \\\\= √(683.4375) \\\\=26.1 \ mm^(2)`