Similar Polygons: Finding Side Length Ratio from Areas 20 and 80

Question

There are two similar polygons.

The area of the first polygon is 20 and the area of the second polygon is 80.

What is the ratio between their lengths of the sides?

Video Solution

Solution Steps

00:00 Find the ratio between the side lengths of the polygons

00:03 Let's label each polygon with A and B

00:15 The square of the similarity ratio equals the ratio of the polygons' areas

00:30 Let's substitute appropriate values and solve

00:43 Let's factor 80 into (4) and (20) and reduce

00:47 This is the similarity ratio squared

01:06 And this is the solution to the question

Answer

1:3

Related Subjects

Similarity of Triangles and Polygons