Understand Similar Figures

All corresponding sides are proportional in similar figures.

• True

• False

All corresponding angles are congruent in similar figures.

• True
• False

All corresponding sides are congruent in any similar figure.

• True
• False

The triangles are similar.  Find x

• 90
• 60
• 30
• 15

Two objects that are the same shape but not the same size are _______.

• Congruent
• Vertical
• Similar
• Complementary 

• A
• B
• C
• D

A triangle is dilated by a scale factor of 2. If the original area was 24, what will be the new area?

• 24

• 2

• 96

• 48

The area of a triangle is 20 square units. If the triangle is dilated by a scale factor of 2, which statement is true?

• The area of the new triangle will be 2 times the area of the old triangle.
• The area of the new triangle will be 3 times the area of the old triangle.
• The area of the new triangle will be 4 times the area of the new triangle.
• The two triangles will have the same area.

A square is dilated by a scale factor of 4.3. Which statement is true?

• The perimeter of the new square will be 8.6 times the perimeter of the old square.

• The perimeter of the new square will be 3 times the perimeter of the old square.

• The perimeter of the new square will be 4.3 times the perimeter of the old square.

• The perimeter of the new square will be 18.49 times the perimeter of the old square.

If a shape is dilated, how do you find the new perimeter?

• You multiply the old perimeter by the scale factor used in the dilation.
• You square the scale factor used in the dilation. Then multiply the old perimeter by the squared scale factor.