Similar Triangles Area and Perimeter

• A
• B
• C
• D

Are the triangles similar?

• Yes

• No

Are the triangles similar?

• Yes

• No

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.

The figures shown are similar. The areas of each figure is given.

What is the ratio of the side length of the smaller triangle to the larger triangle?

• 4:49

• 2:7

• 1:7

• 1:25

The figures below are similar. The labeled sides are corresponding.

What is the perimeter of the smaller triangle?

• 23.8 mm

• 10.2 mm

• 6.67 mm

• 4.3 mm

Find the area of polygon B given similar polygons and the scale factor is shown. Round your answer to the nearest tenth.

• 23.0 m²

• 18 m²

• 18.4 m²

• 12.5 m²

Given polygons A and B are similar with corresponding dimensions shown, what is the area of polygon B?

• 6.67 m²

• 3.33 m²

• 10 m²

• 22.5 m²

Given polygons A and B are similar with corresponding dimensions shown, what is the missing dimension of polygon B?

• 4.1

• 16.7

• 3.3

• 11.1

The scale factor of two similar figures is 4 : 5. What is the ratio of their perimeters?

• 4 : 5

• 16 : 25

• 64 : 125

• 8 : 10