1. The sum of three angles in a triangle is  180360°Angle-Side-AnglecongruentHypotenuseinteriorRight Angle-HypotenusesameSide – Angle – SideSide – Side – Side.

2. The exterior angle of a triangle is equal to the sum of the two  180360°Angle-Side-AnglecongruentHypotenuseinteriorRight Angle-HypotenusesameSide – Angle – SideSide – Side – Side opposite
angles.

3. The exterior angles of a triangle add up to  180360°Angle-Side-AnglecongruentHypotenuseinteriorRight Angle-HypotenusesameSide – Angle – SideSide – Side – Side .

4. Two lines segments are congruent if they have the  180360°Angle-Side-AnglecongruentHypotenuseinteriorRight Angle-HypotenusesameSide – Angle – SideSide – Side – Side length.

5. Two angles are  180360°Angle-Side-AnglecongruentHypotenuseinteriorRight Angle-HypotenusesameSide – Angle – SideSide – Side – Side if the measures of the angles are equal.

6. If the corresponding sides and corresponding angles of two plane figures are equal
then they are called  180360°Angle-Side-AnglecongruentHypotenuseinteriorRight Angle-HypotenusesameSide – Angle – SideSide – Side – Side figures.

7. If three sides of one triangle are equal to the corresponding sides of the other triangle
then the two triangles are congruent. This is known as  180360°Angle-Side-AnglecongruentHypotenuseinteriorRight Angle-HypotenusesameSide – Angle – SideSide – Side – Side criterion.

8. If two sides and the included angle of a triangle are equal to the corresponding
two sides and the included angle of another triangle, then the two triangles are
congruent to each other. This is known as  180360°Angle-Side-AnglecongruentHypotenuseinteriorRight Angle-HypotenusesameSide – Angle – SideSide – Side – Side criterion.

9. If two angles and the included side of one triangle are congruent to the corresponding
two angles and the included side of another triangle, then the triangles are congruent
This is known  180360°Angle-Side-AnglecongruentHypotenuseinteriorRight Angle-HypotenusesameSide – Angle – SideSide – Side – Side criterion.

10. In right angled triangle, the side which is opposite to right angle is the largest side
called  180360°Angle-Side-AnglecongruentHypotenuseinteriorRight Angle-HypotenusesameSide – Angle – SideSide – Side – Side.

11. If the hypotenuse and one side of a right angled triangle is equal to the hypotenuse
and one side of another right angled triangle then the two right angled triangles are
congruent. This is known as  180360°Angle-Side-AnglecongruentHypotenuseinteriorRight Angle-HypotenusesameSide – Angle – SideSide – Side – Side Side criterion