Question

if a ray OC stands on line AB such that ∆AOC =∆COB show that ∆AOC =90°

Answer 1

since triangle AOC= triangle COB
then,
angle AOC= angle BOC
and,
angle AOC+angle BOC=180 degree
2angle AOC=180 degree
angle AOC=90 degree

Answer 2

If triangle AOC and triangle COB are equal
then we can say that AO is equal to OB,so we can understand that OC is perpendicularly bisecting the line AB
therefore angle AOC =90 degree
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