Question

What is the area of triangle DEF?

Answer 1

Answer:

$A=2\sqrt{14}\ units^2$

Step-by-step explanation:

we know that

Heron's Formula is a method for calculating the area of a triangle when you know the lengths of all three sides.  

so

$A=\sqrt{s(s-a)(s-b)(s-c)}$

where

a, b and c are the length sides of triangle

s is the semi-perimeter of triangle

we have

$a=5\ units,b=6\ units,c=3\ units$

Find the semi-perimeter s

s=$\frac{5+6+3}{2}=7\ units$

Find the area of triangle

$A=\sqrt{7(7-5)(7-6)(7-3)}$

$A=\sqrt{7(2)(1)(4)}$

$A=\sqrt{56}\ units^2$

simplify

$A=2\sqrt{14}\ units^2$