Answer
$5.56 \ square \ units $
Work Step by Step
According to Heron's formula, the area of a triangle with sides $a,b$ and $c$ is given by:
$K=\sqrt{s(s-a)(s-b)(s-c)}$
where $s=\dfrac{a+b+c}{2}$
Therefore, $s=\dfrac{4+4+3}{2}=5.5$
In order to find the area of the triangle, we will have to substitute the data into Heron's formula.
$K=\sqrt{5.5(5.5-4)(5.5-4)(5.5-3)} \approx 5.56 \ square \ units $