Similar Figures

What is true about the shape and size of similar figures?

• Same shape and same size
• Same shape and not the same size
• Different shape and same size
• Different shape and not the same size

The term "congruent" means ...

• matching
• similar
• corresponding
• equal

What is true about the sides of similar figures?

• Corresponding sides are proportional.
• Corresponding sides are congruent.
• Opposite sides are proportional.
• Opposite sides are congruent.

What is true about the angles of similar figures?

• Corresponding angles are proportional.
• Complementary angles are proportional.
• Corresponding angles are congruent.
• Complementary angles are congruent.

This symbol stands for ...

• similar
• congruent
• proportional
• corresponding

This symbol stands for ...

• is corresponding to
• is proportional to
• is congruent to
• is similar to

What does congruent mean?

• same shape and same size

• same size

• sames shape

• neither

Answer explanation

Two figures are congruent if they are the exact same and have the exact same size. Two angles are congruent if they have the same measure. Two side lengths are congruent if they have the same measure.

Are the following similar? Why or why not?

• Yes

• No, the corresponding angles are not equal.

• No, the ratios of the corresponding sides are not equal.

Answer explanation

They are not similar because one shape has a ratio (long side:short side) of 6:2 while the other is 6:4. For two polygons to be similar, the corresponding sides must be proportional (same ratio)

The pair of figures is similar. Find the missing side.

• x = 20

• x = 12

• x = 5

• x = 4

Answer explanation

The ratio of the short sides is 12/3 which means you divide the large triangle by 4 to find the length of the smaller triangle. 20/4 = 5

The two right triangles below are similar. What is x, the missing side length in triangle DEF?

• 3.75

• 9.75

• 10

• 12

Answer explanation

HINT: Use corresponding sides to set up a proportion