Characteristics of Triangles + One Unique, Many, No Triangles NOTES & PRACTICE

This resource was created to PARTIALLY meet the requirements for the 7th Grade Math Geometry Standard below:

CCSS.MATH.CONTENT.7.G.A.2

Draw (freehand, with ruler and protractor, and with technology) geometric shapes with given conditions. Focus on constructing triangles from three measures of angles or sides, noticing when the conditions determine a unique triangle, more than one triangle, or no triangle.

This resource contains the following items:

1) Understanding Triangle Side Lengths NOTES & PRACTICE

· (Triangle Inequality Theorem) Students will learn the basics of the triangle inequality theorem, focusing on comparing the sum of the two shorter sides with the longest side* to determine which sets of side lengths could possibly form a triangle.

2) Understanding Triangles & Interior Angles NOTES & PRACTICE

· Students will learn the requirements of interior angles of triangles.

3) One, None, or Many Triangles? NOTES & PRACTICE

· Students will apply the theorems for side lengths and angles to determine if any given set of measurements (side lengths or interior angles) could form one unique triangle, many triangles, or no triangles.

4) Triangles TEST PRACTICE (Printable and version for Google Forms)

5) Answer Key to All Parts

*Please Note: The official Triangle Inequality Theorem states that the sum of any two sides of a triangle must be greater than the third side and has students test all three combinations. I have found that having students at this level focus on comparing the sum of the shorter sides to the longest side is much less confusing for them. Having students test all possible combinations is NOT included in this resource.