Digits, Grade 8, Volume 2, Homework Helper

10-3: Relating Similar Triangles and Slope

Part 1

Example Comparing Triangles to Their Dilations

Draw the triangle that is the image of the given triangle after a dilation with center (0,22) and a scale factor of 2. Look at the ratio of the rise to the run of each triangle. How do the ratios compare? Explain.

A graph of a triangle with vertices (0, −2), (2, −1), and (2, 1).

Solution

The ratio of the rise to the run of the given triangle is 3 halves . The ratio of the rise to the run of the image triangle is 6 fourths , which is equivalent to 3 halves . So, the ratios of the rise to the run of the two triangles are the same.

The image triangle after a dilation with center (0, −2) and a scale factor of 2 has vertices (0, −2), (4, −2), and (4, 4).


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Table of Contents

Digits, Grade 8, Volume 2, Homework Helper Unit D: Two-Dimensional Shapes Unit E: Measurement and Data Unit F: Personal Financial Literacy Unit G: Step-Up Lessons English/Spanish Glossary Formulas Math Symbols Formulas Measures Properties