1. Joianna Wallace Pd:1 Extra Credit
Geometry Study Guide
Joianna Wallace
Pd:1
Extra Credit

2. Types Triangle Acute Triangle Obtuse Triangle Right Triangle
Scalene Triangle
Isosceles Triangle
Equilateral Triangle
Equiangular Triangle

3. Acute Triangle
A triangle where all three angles are less than ninety degrees

4. Obtuse Triangle
A triangle where one of the sides is over ninety degrees

5. Right Triangle A triangle where one of the angles is ninety degrees
Parts-Legs and hypotenuse

6. Scalene Triangle
A triangle with no equal sides, so every side and angle is a different length

7. Isosceles Triangle
A triangle with at least two equal sides and angles.

8. Equilateral Triangle
A triangle in which all three sides are congruent

9. Equiangular Triangle A triangle where all three angles are congruent.
*Note: Most equiangular triangles are equilateral.

10. Triangle Inequality Postulate
The sum of the lengths of any two sides of a triangle must be greater than the third side

11. Triangle Inequality Postulate
Is ABC a triangle?

12. Triangle Inequality Postulate
AC+CB=10; 10>7; Therfore ABC is a triangle by the Triangle Inequality Postulate.

13. Triangle Sum Theorem
The sum of the interior angles of any triangle is equal to 180 degrees

14. Triangle Sum Theorem
Based on the Triangle Sum Theorem, what is the value of x?

15. Triangle Sum Theorem
The Triangle Sum Theorem states all angles equal 180 degrees. Angle A plus Angle C equals 95 degrees. So by this theorem Angle B is
85 degrees.

16. Third Angle’s Theorem
If two angles of one triangle are congruent to two angles of a second triangle, then the third angles are also congruent

17. Third Angle’s Theorem
Is Triangle PQR congruent to Triangle LJK?

18. Third Angle’s Theorem
The Third Angles Theorem states that if two angles of one triangle are congruent to two angles of another triangle, then the third angles of the triangles are congruent also.

19. Side Side Side Theorems
If all three sides of one triangle are congruent to all three sides of a second triangle, then the two triangles are congruent

20. Side Angle Side Theorem
If two sides and the included angle of one triangle are congruent to two sides and the included side of a second triangle, then the two triangles are congruent

21. Angle Side Angle Theorem
If two sides and the included angle of one triangle are congruent to two angles and the included side of another triangle, then the triangles are congruent

22. Angle Angle Side Theorem
If two angles and a non-included side of one triangle is congruent to two angles and a non-included side of another triangles are congruent.

23. Hypotenuse Leg Theorem
if the hypotenuse and a leg of one right triangle are congruent to the hypotenuse and a leg of a second right triangle, then the triangles are congruent.

24. Corresponding Parts of Congruent Triangles are
CPCTC
Corresponding Parts of Congruent Triangles are

25. CPCTC Ex. Given: AC\\DB and P is the midpoint of CD
Prove:   CP is congruent to DP

26. CPCTC Proof: Statement Reason Given
Alternate interior angles are congruent
  P is the midpoint of CD
Definition of "midpoint"
Vertical angles are congruent
ASA
CPCTC

27. Isosceles Triangle Theorem
If two sides of a triangle are congruent, the angles opposite them are congruent.

28. Converse of Isosceles Triangle Theorem
If two angles of a triangle are congruent, the sides opposite them are congruent. 

29. Overlapping Triangles
Given:
Prove:

30. Overlapping Triangles
Given
Substitution Post.