Exploring Area and Perimeter in Similar Figures

The video tutorial discusses the concepts of area and perimeter in similar figures, emphasizing that similar figures have proportional sides and equal angles. It explains how to calculate the perimeter by multiplying the side ratio and how to find the area by squaring the side ratio. The tutorial also covers finding unknown dimensions using given perimeter ratios.

What defines similar figures in geometry?

• Figures with proportional sides and equal angles

• Figures with the same area

• Figures with the same perimeter

• Figures with the same color

Tags

CCSS.8.G.A.2

CCSS.HSG.CO.B.6

How do you calculate the perimeter of a larger similar figure when you know the perimeter of a smaller one?

• Divide by the ratio of their sides

• Multiply by the ratio of their sides

• Subtract the ratio from the original perimeter

• Add the ratio to the original perimeter

What is the perimeter of a larger triangle if the smaller one has a perimeter of 5 yards and the side length ratio is 1:5?

• 20 yards

• 15 yards

• 10 yards

• 25 yards

In similar figures, if the side length ratio is 4:9, what is the area ratio?

• 16:81

• 2:3

• 4:9

• 8:18

How do you find the area of a similar figure when you know the area of another?

• Divide the known area by the side length ratio

• Subtract the side length ratio from the known area

• Multiply the known area by the square of the side length ratio

• Add the side length ratio to the known area

If a square has an area of 81 sq ft and a similar square has sides 4/9 the length, what is the area of the smaller square?

• 64 sq ft

• 36 sq ft

• 16 sq ft

• 9 sq ft

What happens to the area when the side lengths are doubled?

• It doubles

• It stays the same

• It triples

• It quadruples

Tags

CCSS.7.G.A.1

How do you calculate the area of a figure when the side length ratio is known?

• None of the above

• Square the side length ratio and multiply by the known area

• Multiply the side length ratio by the known area

• Divide the known area by the side length ratio

Tags

CCSS.7.G.A.1

If the perimeter ratio of two similar figures is 7:3, what is the side length ratio?

• 7:3

• 3:7

• 1:1

• 2:1

Given a side length of 3 cm and a perimeter ratio of 7:3, what is the length of the corresponding side in the larger figure?

• 7 cm

• 9 cm

• 21 cm

• 3 cm