Section 5 Congruent Polygons.notebook
January 10, 2014
Bellringer:
1) A scale model of a building is constructed using the scale of 2 in: 40 ft. The actual height of the building is 240 ft. Find the height of the scale model.
2) The model of a jet plane is 2.5 ft long. The scale of the model is 1 : 40. What is the actual length of the plane?
Section 5 Congruent Polygons.notebook
Unit 3
Congruent Polygons
January 10, 2014
Section 5 Congruent Polygons.notebook
January 10, 2014
Congruent Polygons Congruent Polygons ­ geometric figures that have the same size and shape
Do you remember the symbol for congruent?
Line segments are congruent when they have the same length.
3 in.
A
C
3 in.
AB ≅ CD
D
B
Angles are congruent when they have the same degree measure.
X
112
o
112
o
X ≅ Y
Y
Triangle ABC is congruent to triangle XYZ
B
ABC ≅ XYZ
A
Corresponding Angles
Z
C
X
Y
Corresponding Sides
Section 5 Congruent Polygons.notebook
January 10, 2014
Use the figures at the right to complete each statement:
S
P
1) SP ≅ ___
2) B ≅ ___
3) Parallelogram PQRS ≅ Parallelogram ____
R
Q
4) If the length of DB is 15 cm, then the length
of _____ is 15 cm.
D
o
o
5) If m R = 98 , then m ____ = 98
C
A
B
Section 5 Congruent Polygons.notebook
January 10, 2014
Use the figure at the right. Suppose you are given the information that DEF ≅ XYZ
Z
X
1) Make a sketch of DEF.
Y
2) Which side of DEF would have three marks?
3) Which angle of DEF would have two marks?
4) Which angle of DEF would be a right angle?