Find the triangle

1. The problem statement, all variables and given/known data

If in any triangle r=r1-r2-r3, then which type of triangle is it?

r1,r2,r3 denotes ex-radii.



3. The attempt at a solution



4R = r1+r2+r3-r



r2+r3 = 2R



I can't figure out what to do next.