2. Isosceles Triangle ABC Vertex Angle Leg Base Base Angles

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4. Theorem 4.6-Base Angles Theorem If two sides of a triangle are congruent, Then, the angles opposite them are congruent.

5. Prove Theorem 4.6 Given: Prove:

6. Theorem 4.6-Base Angles Theorem The converse: If two sides of a triangle are congruent, Then, the angles opposite them are congruent.

7. Theorem 4.7-Converse of the Base Angles Theorem If two angles of a triangle are congruent, Then the sides opposite them are congruent.

8. Prove Theorem 4.7 Given: Prove:

9. Now that you know about these theorems….test yourself with some problems…

15. Solve for x and y

18. Corollary to theorem 4.6 & 4,7 If a triangle is equilateral, Then it is equiangular If a triangle is equiangular Then it is equilateral.

19. Theorem 4.8-Hypotenuse-Leg (HL) Congruence Theorem If the hypotenuse and leg of a right triangle are congruent to the hypotenuse and leg of a second right triangle, Then the two triangles are congruent.

20. Solve for x

23. Write the equation of the line Passing through P(1,1) and Perpendicular to y = -3x - 4

24. Given the points (5,8) & (-12,1) What is the distance between them? What are the coordinates of the midpoint?

25. Assignment 4.6