Area of Similar Triangles

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

Find the area of polygon B given similar polygons and the scale factor shown.

• 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

A tree is 12 feet tall and casts a shadow 9 feet long. A building nearby casts a shadow that measures 21 feet. How tall is the building? (Draw a picture, set up a proportion)

• 16 feet

• 21 feet

• 24 feet

• 28 feet

Identify the perimeter and area ratios for the following figures.

• Per. Ratio=8  Area Ratio=64

• Per. Ratio=8/48  Area Ratio=64/2304

• Per. Ratio=8/48  Area Ratio=8/48

• Per. Ratio=8/48  Area Ratio=2304/64

Complete each proportion.
CB / DM  =  AC / ?

• BM

• MA

• BC

• AD

• 3.6 cm

• 6 cm

• 6.4 cm

• 7.2 cm

Find side length X.

• 22.5

• 10

• 9

• 7.5

• AA
• SAS
• SSA
• SSS