1. The triangular face of the Rock and Roll Hall of Fame in Cleveland, Ohio, is isosceles. The length of the base is 229ft. 6 in. What is the length of the highlighted line that lies at the halfway point of both legs of the triangle?

2. 5.2: Bisectors in Triangles
LEQ: How do we use bisector theorems to find lengths in triangles?

3. Bisectors in Triangles
Perpendicular Bisector Theorem
If a point is on the perpendicular bisector of a segment, then it is equidistant from the endpoints of the segment.
Angle Bisector Theorem
IF a point is on the bisector of an angle, then the point is equidistant from the sides of the angle.

4. Example
According to the diagram, how far is K from EH? From ED? What can you conclude about EK? Find the value of x. Find m<DEH. D
(2x)˚ E K 10
(x + 20)˚ H

5. Solve for x: T Y 2x Z
3x-5 W

6. Work with a partner to answer the questions:CD is the perpendicular bisector of ST and XD. Justify your answers. C
CT=
12, SAS, CPCTC
SX=
4, segment ad.
MT=
5, P.B.T.
DY=
7, P.B.T.
TY=
4,segment ad.
CX=
16 SAS, CPCTC
ST=
10, seg. Ad.
XY=
14, seg. Ad. 12 16 S T 5 M X 7 Y D

7. Pg
1-4,6-11,27-30,45-48
Choose: 40 and 43 OR 41 and 44