find the length of the third side. if necessary, write in simplest radical form.

Answer:
6
Step-by-step explanation:
its a right angle so to find a side use a Pythagorean theorem
Pythagorean theorem =
[tex]a^2+b^2=c^2[/tex]
[tex]a^2+b^2[/tex] are the sides
[tex]c^2[/tex] is the hypotenuse
In this case we need the hypotenuse
[tex]3\sqrt{3} ^2 + 3^2 = c^2[/tex]
[tex]27 + 9=c^2[/tex]
[tex]36=c^2[/tex]
the opposite of squaring is square rooting so:
[tex]\sqrt{36} =6[/tex]
therefore the answer is 6 ^-^