Similar figures have the same shape but not size, with the same ratio of corresponding side lengths. Congruent figures have the same shape and size. The ≅ symbol indicates figures are similar, while the = symbol shows they are congruent. Similar triangles problems involve finding side length ratios, while congruent figure problems involve determining specific side lengths using corresponding parts of the same position between figures.

1. Similar and Congruent Figures

2. Similar and Congruent Figures
• Similar figures have the same shape, but not
the same size. They must have the same ratio
of side lengths
• Congruent figures have the same shape and
the same size
• Corresponding parts are the sides or angles
that have the same position.

3. • The symbol means that the shapes are
similar
• The symbol means that the shapes are
congruent
≅

4. Similar Triangles

5. Similar Triangles
3
4
5
6
10
8
What is the ratio of sides?

6. Congruent Figures
A
B
C
D
E
F
12
8
What is the length of EF
What is the length of BC

7. Similar Figures
A
B
C
D
E
F
G
H
FIGURE 1
Figure 2
Side AB is similar to side ________
Side BD is similar to side ________

8. Similar Figures
A
B
C
D
E
F
G
H
FIGURE 1
Figure 2
What is the ratio of the sides________
What is the length of side AC?
15
10
6
12
What is the length of side EH?