I don't understand your question:

1. IfAB=5 BC=4 CA=3are the measures of the lengths of the sides then ABC is a right triangle with AB as hypotenuse.

2. It's this statemant:CB is going with the angel of 200 degreeswhich I don't understand. To determine an angle you need:

- three points

- two straight lines

- an arc

- two curves

- ....

Please tell us exactly where this angle of 200° is to be found. Maybe you can provide us with a sketch(?)