+
Lesson Plan
EngageNY

Triangle Congruency Proofs (part 2)

For Teachers 9th - 10th Standards
Looking to challenge your students that have mastered basic triangle congruence proofs? A collection of proofs employ previously learned definitions, theorems, and properties. Pupils draw on their past experiences with proofs to...
+
Lesson Plan
EngageNY

Triangle Congruency Proofs (part 1)

For Teachers 9th - 10th Standards
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...
+
Unit Plan
1
1
EngageNY

Congruence, Proof, and Constructions

For Teachers 8th - 10th Standards
This amazingly extensive unit covers a wealth of geometric ground, ranging from constructions to angle properties, triangle theorems, rigid transformations, and fundamentals of formal proofs.  Each of the almost-forty lessons is broken...
+
Instructional Video16:33
2
2
Flipped Math

More with Proofs

For Students 9th - 12th Standards
Proofs may be as easy as 1, 2, 3 ... maybe. Pupils participate in creating four example proofs. The presentation uses a list of geometric properties to develop the proofs by filling in both the statements and reasons. Scholars practice...
+
Instructional Video6:57
2
2
Flipped Math

Unit 2 Review: Reasoning and Proofs

For Students 9th - 12th Standards
The proof is in the review. Individuals watch a short review of the content from the unit to prepare for the unit exam. The review covers inductive reasoning, conditional and related statements, and two-column algebraic and geometric...
+
Instructional Video9:11
Corbett Maths

Algebraic Proof

For Students 8th - 12th Standards
Proofs do not exist only in geometry. The video shows the class different ways that proofs appear in algebra. Pupils work through a variety of algebraic proofs involving the divisibility of an algebraic expression or whether it is even...
+
Instructional Video0:53
Corbett Maths

Angles in the Same Segment – Proof

For Students 8th - 12th Standards
If angles intercept the same arc, the angles must be the same size. The quick video talks through the proof of showing the reason two inscribed angles that intersect the same arc have the same measurement. Pupils then create their own...
+
Worksheet
Curated OER

Proofs Of The Pythagorean Theorem?

For Students 8th Standards
Even U.S. President James Garfield had his own proof of the Pythagorean Theorem! Pupils consider three different attempts at a geometric proof of the Pythagorean Theorem. They then select the best proof and write paragraphs detailing...
+
Lesson Plan
EngageNY

Informal Proofs of Properties of Dilations

For Teachers 8th Standards
Challenge the class to prove that the dilation properties always hold. The lesson develops an informal proof of the properties of dilations through a discussion. Two of the proofs are verified with each class member performing the...
+
Lesson Plan
EngageNY

Informal Proof of the Pythagorean Theorem

For Students 8th Standards
Prove the Pythagorean Theorem using multiple informal proofs. Scholars first develop an understanding of the origins of the Pythagorean Theorem through proofs. They round out the instructional activity by using the theorem to find...
+
Assessment
Mathed Up!

Proof

For Students 9th - 12th Standards
Scholars learn how to write number theory proofs by viewing a video reviewing techniques for proofs on divisibility, parity, and consecutive integers. They then write proofs for a handful of conjectures on a learning exercise.
+
Activity
Education Development Center

Proof with Parallelogram Vertices

For Teachers 8th - 10th Standards
Geometric figures are perfect to use for proofs. Scholars prove conjectures about whether given points lie on a triangle and about midpoints. They use a provided dialogue among fictional students to frame their responses.
+
Lesson Plan
EngageNY

Proof of the Pythagorean Theorem

For Teachers 8th Standards
What does similarity have to do with the Pythagorean Theorem? The activity steps through the proof of the Pythagorean Theorem by using similar triangles. Next, the teacher leads a discussion of the proof and follows it by an animated...
+
Handout
Lockport City School District

Reasons for Geometric Statement/Reason Proofs

For Students 8th - 11th Standards
Stuck trying to remember the formal language of a geometric proof? Never fear, this handout has them all ready to go. The reasons are sectioned by topic so this handy guide is ready when you are to tackle those two column proofs. 
+
Lesson Plan
Curated OER

Proof of the Pythagorean Theorem Using Transformations

For Teachers 9th - 12th Standards
Middle and high schoolers construct a triangle using Cabri Jr. They construct squares on each of the legs and hypotenuse of the triangle. Pupils show that the area of the squares on the leg equal the area of the square on the hypotenuse.
+
Unit Plan
Mathematics Vision Project

Geometric Figures

For Teachers 10th - 12th Standards
Logical thinking is at the forefront of this jam-packed lesson, with young mathematicians not only investigating geometric concepts but also how they "know what they know". Through each activity and worksheet, learners wrestle with...
+
Lesson Plan
Curated OER

Euclidean Direct Proofs

For Teachers 9th - 10th
Learning how to prove theorems in geometry can be challenging. This resource explains what a proof is, and the different styles for proofs. It also contains links to web-based practice problems that help guide learners though example...
+
Worksheet
Curated OER

Proofs

For Students 8th - 11th
In this geometric proof instructional activity, students compose 20 triangle congruency proofs. Students will decide if there is enough information in problems 1-6 to prove if any triangles are congruent. In problems 17 to 20, students...
+
Lesson Plan
Curated OER

Indirect Proof and Inequalities in one Triangle

For Teachers 10th
In this geometry worksheet, 10th graders complete an indirect proof and order the sides or angles of a triangle. Also, students determine if a triangle can have sides with the given lengths. The two page worksheet contains twelve...
+
Worksheet
Curated OER

Extra Practice with Proofs

For Students 9th - 11th
In this practice with proofs learning exercise, students give a reason for each step of a proof. They complete missing portions of a proof. This one-page learning exercise contains three multi-step problems.
+
Unit Plan
Mathematics Vision Project

Congruence, Construction and Proof

For Teachers 9th - 10th Standards
Learn about constructing figures, proofs, and transformations. The seventh unit in a course of nine makes the connections between geometric constructions, congruence, and proofs. Scholars learn to construct special quadrilaterals,...
+
Unit Plan
Mathematics Vision Project

Module 2: Congruence, Construction and Proof

For Teachers 9th - 12th Standards
Construct yourself a winning geometry unit. A set of lessons introduces geometry scholars to constructions and proofs with compasses and straightedges. It also covers triangle congruence through transformations. This is the second of...
+
Lesson Plan
West Contra Costa Unified School District

Simplify Expressions and Solve Equations Using Two-Column Proofs

For Students 8th - 10th Standards
Increase understanding of the algebraic properties and their importance. Scholars justify their steps as they simplify expressions and solve equations. They formalize their work as two-column proof.
+
Lesson Plan
EngageNY

Informal Proof of AA Criterion for Similarity

For Teachers 8th Standards
What does it take to show two triangles are similar? The 11th segment in a series of 16 introduces the AA Criterion for Similarity. A discussion provides an informal proof of the theorem. Exercises and problems require scholars to apply...

Other popular searches