Cody found the sum of the exterior angles to be 380°. Did Cody make an error? If so describe it. No, Cody did not make an error. The sum of the exterior angles of a triangle should be 380°. Yes, Cody made an error adding the three exterior angles together. Yes, Cody made an error drawing the exterior angles. The 145° angle is not an exterior angle. Yes, Cody made an error drawing the exterior angles. The 100° angle is not an exterior angle.