1. Classify the triangle. A. scalene B. isosceles C. equilateral
5-Minute Check 1

2. Find x if mA = 10x + 15, mB = 8x – 18, and mC = 12x + 3.
5-Minute Check 2

3. Name the corresponding congruent sides if ΔRST  ΔUVW.
A. R  V, S  W, T  U
B. R  W, S  U, T  V
C. R  U, S  V, T  W
D. R  U, S  W, T  V
5-Minute Check 3

4. Name the corresponding congruent sides if ΔLMN  ΔOPQ.B. C. D. ,
5-Minute Check 4

5. 5-Minute Check 5-Minute Check 6
Find y if ΔDEF is an equilateral triangle and mF = 8y + 4.
A. 22 B
C. 7
D. 4.5
5-Minute Check 5-Minute Check 6

6. You used segment and angle bisectors.
Identify and use perpendicular bisectors in triangles.
Identify and use angle bisectors in triangles.
Then/Now

7. Concept

8. Use the Perpendicular Bisector Theorems
A. Find BC.
Example 1

9. Use the Perpendicular Bisector Theorems
B. Find XY.
Example 1

10. Use the Perpendicular Bisector Theorems
C. Find PQ.
Example 1

11. A. Find NO.
A. 4.6
B. 9.2
C. 18.4
D. 36.8
Example 1

12. B. Find TU.
A. 2
B. 4
C. 8
D. 16
Example 1

13. C. Find EH.
A. 8
B. 12
C. 16
D. 20
Example 1

14. Concept

15. Use the Angle Bisector Theorems
A. Find DB.
Example 3

16. Use the Angle Bisector Theorems
B. Find mWYZ.
Example 3

17. Use the Angle Bisector Theorems
C. Find QS.
Example 3

18. A. Find the measure of SR.
A. 22
B. 5.5
C. 11
D. 2.25
Example 3

19. B. Find the measure of UV.
A. 7
B. 14
C. 19
D. 25
Example 3

20. C. Find the measure of HFI.
B. 30
C. 15
D. 30
Example 3

21. Concept

22. Concept

23. A. Find ST if S is the incenter of ΔMNP.
Use the Incenter Theorem
A. Find ST if S is the incenter of ΔMNP.
Example 4

24. B. Find mSPU if S is the incenter of ΔMNP.
Use the Incenter Theorem
B. Find mSPU if S is the incenter of ΔMNP.
Example 4

25. A. Find the measure of GF if D is the incenter of ΔACF.
B. 144
C. 8
D. 65
Example 4

26. Example 4End of the Lesson
B. Find the measure of BCD if D is the incenter of ΔACF.
A. 58°
B. 116°
C. 52°
D. 26°
Example 4End of the Lesson