Ray su is an angle bisector of ∠rst. the measure of ∠tsu is 42°. what is the measure of ∠rsu? 90° 84° 42° 168°

RSU is also 42 because SU is the angle bisector so it divided RST in two equal halves.

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1. statement- ca is parallel to db and e is the midpoint of ad reason- given2. statement- reason- alternate interior angles3. statement- de is congruent to ae reason- definition of midpoint4. statement- triangle aec is congruent to triangle deb reason- asa (angle side angle)