Question

What do I need to subtract from to get angle two?

Answer 1

Step 1) Add up the three given angles: 125+109+83 = 317

Step 2) Subtract the result (found in step one) from 360
360 - 317 = 43

The reason for the 360 is because for any four-sided polygon, the angles always add up to 360 degrees. 

The answer is 43