Answer
$3921.3 \ m$
Work Step by Step
Since, we know the one angle and two sides of the triangle , therefore we will use the Law of cosines to compute the side (a).
$a^2=b^2+c^2- 2bc \cos A$
Plug in the given data, so we get as follows:
$a^2=(3428)^2+(5631)^2- 2(3428)(5631) \cos 43.33^{\circ}= 15376718.01$
This yields: $a=\sqrt {15376718.01} = 3921.3 \ m$
