Play around with the applet above. What do you notice about the angles, sides, and perimeters?
The value of the black slider is the "scale factor" of the similarity from quadrilateral ABCD to quad A'B'C'D'. How does this relate to the side lengths, angles, and perimeters?
Write a ratio comparing the perimeter of the polygon on the left to the perimeter of the polygon on the right. Now write a ratio comparing the perimeter of the polygon on the right to the perimeter of the polygon on the left. Simplify the ratios. What do you notice?
[size=150][size=100]Create your own polygon by first drawing vertices with the tool labeled "A." Click on the triangle and click on "Polygon." Connect your vertices to create a polygon. Use the "Angle" tool to find each angle measure of your polygon. Then find the "Distance or Length" tool (same button as the angle) to determine the length of each side. [/size][/size]
Find the side lengths, perimeter, and angles of two similar polygons. What are their scale factors?
Recap: What does it mean for two polygons to be similar? What is a scale factor?
Open your textbook to p. 248-249. Did your definitions align with the formal definitions provided in the book?