Determining Similarity in Figures

The video tutorial covers the concept of similar figures, focusing on identifying corresponding parts such as angles and sides. It explains how similar figures have congruent angles and proportional sides. The tutorial provides examples and non-examples of similar figures and demonstrates how to set up within and between ratios to determine similarity. Two examples are worked through: one showing similar figures and another showing non-similar figures. The video concludes with instructions for student practice.

What is the main characteristic of similar figures?

• They are the same size.

• They are the same shape but not necessarily the same size.

• They have the same area.

• They have the same perimeter.

Which of the following statements is true about corresponding angles in similar figures?

• They are always supplementary.

• They are always proportional.

• They are always congruent.

• They are always different.

In the context of similar figures, what does it mean for sides to be proportional?

• The sides are perpendicular.

• The sides are parallel.

• The sides have the same ratio.

• The sides are equal in length.

Which of the following is an example of a within ratio?

• 6/7 from one figure and 10/20 from another figure.

• 6/7 from one figure and 7/14 from another figure.

• 6/7 from one figure and 12/14 from the same figure.

• 6/7 from one figure and 12/14 from another figure.

What is a between ratio?

• A ratio set up with two angles from the same figure.

• A ratio set up with two angles from different figures.

• A ratio set up with two corresponding sides from different figures.

• A ratio set up with two sides from the same figure.

How do you determine if two figures are similar using cross products?

• By dividing the products of the sides.

• By adding the products of the sides.

• By subtracting the products of the sides.

• By setting the cross products equal to each other.

In the example given, what is the within ratio for triangle ABC?

• 4/8

• 10/14

• 4/10

• 8/10

What is the between ratio for the pink sides of the two triangles?

• 4/8

• 4/5

• 8/10

• 10/14

In the practice problem, what is the combined length of the side on the large triangle?

• 15

• 22

• 10

• 14

What should you do to determine if the figures in the practice problem are similar?

• Check if the figures are the same size.

• Set up within and between ratios and solve the proportions.

• Measure the angles of the figures.

• Compare the areas of the figures.