Curated OER
Finding the Measure of Segments
Young scholars observe and solve examples of betweenness, ruler postulate, and segment addition postulate. They complete the Finding the Measure of Segments worksheet using the distance formula.
Curated OER
Measuring Angles & Segments
Students view a PowerPoint for a warm-up lesson. They practice measuring around the classroom, measuring such things as the length and width of a desk, pencil, door, and book. Students use a website to practice measuring angles.
Curated OER
Measuring Length: Practice A
Ninth graders investigate the segment addition postulate. In this geometry lesson, 9th graders explore the difference between equal and congruent in relation to segment length. The lesson includes an algebra application and a...
EngageNY
Triangle Congruency Proofs (part 1)
Can they put it all together? Ninth graders apply what they know about proofs and triangle congruence to complete these proofs. These proofs go beyond the basic triangle congruence proofs and use various properties, theorems, and...
Curated OER
Triangle Inequality Theorems Investigation
Students estimate and measure triangles. In this geometry lesson, students identify the relationship between three sides and a triangle. They use the inequality theorem to decide if a triangle will be formed or not.