Draw an angle bisector from a to a point d such that d is on bc. then, use the triangle sum theorem to show m∠a=m∠c.
draw an angle bisector from a to a point d such that d is on bc. then, show that corresponding sides and the angle between these sides of new triangles adb and adc are congruent. finally, use the side-angle-side congruence postulate and the definition of congruent angles to show m∠a=m∠c.
draw an angle bisector from b to a point d such that d is on ac. then, show that corresponding sides and the angle between these sides of new triangles abd and cbd are congruent. finally, use the side-angle-side congruence postulate and the definition of congruent angles to show m∠a=m∠c.
draw an angle bisector from b to a point d such that d is on ac. then, show that corresponding sides of new triangles abd and cbd are congruent. finally, use the side-side-side congruence postulate and the definition of congruent angles to show m∠a=m∠c.