Prove that the angle between internal bisector of one base angle and the external bisector of the other base angle of a triangle is equal to one-half of the vertical angle.

Prove that the internal bisectors of the angles of a triangle are concurrent

If one angle of a triangle is equal to the sum of the other two angles, then the triangle is

Prove that the internal bisector of the angle A of a triangle ABC divides BC in the ratio AB:AC

If the bisector of the exterior vertical angle of a triangle be parallel to the base. Show that the triangle is isosceles.

If the bisector of the exterior vertical angle of a triangle be parallel to the base. Show that the triangle is isosceles.

Prove that the bisectors of the interior angles of a rectangle form a square.

If the bisector of an angle of a triangle bisects the opposite side, prove that the triangle is isosceles.

Which of the following statements are true (T) and which are false (F): Side opposite to equal angles of a triangle may be unequal. Angle opposite to equal sides of a triangle are equal. The measure of each angle of an equilateral triangle is 60^0 If the altitude from one vertex of a triangle bisects the opposite side, then the triangle may be isosceles. The bisectors of two equal angles of a triangle are equal. If the bisector of the vertical angle of a triangle bisects the base, then the triangle may be isosceles. The two altitudes corresponding to two equal sides of a triangle need not be equal. If any two sides of a right triangle are respectively equal to two sides of other right triangle, then the two triangles are congruent. Two right triangles are congruent if hypotenuse and a side of one triangle are respectively equal to the hypotenuse and a side of the other triangle.

The bisectors of base angles of a triangle cannot enclose a right angle in any case.

The bisectors of base angles of a triangle cannot enclose a right angle in any case.