This question was asked in Ex 14.1, 3
Using your protractor draw an angel BAC of measure 120 degree. With this aangle as given, draw an angle of measure 90 degree. Verify by measurement. [HINT :  1draw a ray AX, the bisector of angle BAC. 2 draw a ray AY, the bisector of angle CAX. 3  Then BAY is the required angle. ]
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