Question

Please explain any one of them

Answer 1

3 Rd one is obtuse angle remaining all are acute angles

Answer 2

HEY MATE

HERE IS YOUR ANSWER

1ST, 2ND AND 4TH ARE ACUTE ANGLES

AND 3RD IS OBTUSE ANGLE

PUT YOUR COMPASS NEEDLE ON THE POINT OF INTERSECTION AND MAKE ONE ARC CROSSING THE TWO ADJACENT LINES.

THEN (WITHOUT CHANGING THE RADIUS) PLACE THE NEEDLE ON THE INTERSECTION OF ARC AND ONE LINE AND MAKE ONE ARC.

NOW PLACE THE NEEDLE ON THE INTERSECTION OF FIRST ARC AND ANOTHER LINE AND MAKE ONE ARC INTERSECTING SECOND ARC.

THE POINT YOU WILL GET BY THE INTERSECTION OF SECOND AND THIRD ARCS IS THE POINT ON THE BISECTER.

SO, NOW JOIN THE POINT OF INTERSECTION OF THE INITIAL TWO LINES AND THE POINT OF INTERSECTION OF THE 2ND AND 3RD ARCS AND YOU WILL GET THE BISECTER.

HOPE THIS HELPS YOU

^_^