Hello!
You can use this by using the Pythagorean theorem

c is the hypotenuse which is the angle opposite the right angle
a and b are the other two sides
you put the values in that you know

square the numbers
5184 +

= 6084
Subtract 5184 from both sides

= 900
Take the square root of 900
square root of 900 = 30
The answer is 30
Hope this helps!