Question

Find the area of a triangle with a =4, b =6, and c =8.

a. 10.2 units 2
b. 8.4 units 2
C.12.4 units
d. 11.6 units 2

Answer 1

d

Explanation:

Given 3 sides of the triangle the area (A) can be calculated using Hero's formula.

A =
`√(s(s-a)(s-b)(s-c))`

where s is the semi perimeter of the triangle

s =
`(a+b+c)/(2)` =
`(4+6+8)/(2)` =
`(18)/(2)` = 9 , thus

A =
`√(9(9-4)(9-6)(9-8))`

=
`√(9(5)(3)(1))`

=
`√(135)`

≈ 11.6 units² → d