Khan Academy
Khan Academy: Geometry: Circumcenter of a Triangle
Explains using multiple proofs that a point on a perpendicular bisector is equidistant from the endpoints of the segment it bisects. Proofs use triangle congruency postulates. Lays the foundation for understanding the circumcenter of a...
Khan Academy
Khan Academy: Geometry: Right Triangles Inscribed in Circles (Proof)
This video tutorial [5:35] explains that if the diameter of a circle is one of the sides of a triangle inscribed in the circle then the triangle is a right triangle. This video also appears in the strand Geometry: Circles.
Khan Academy
Khan Academy: Geometry: Ca Geometry: Pythagorean Theorem, Compass Constructions
This video tutorial demonstrates solutions to problems #51-55 of the California Geometry released state test questions. Problems address proving and using the Pythagorean theorem and compass constructions. [12:35]
Khan Academy
Khan Academy: Geometry: Corresponding Angle Equivalence Implies Parallel Lines
Proof by contradiction that if two lines cut by a transversal create congruent corresponding angles then the lines are parallel. [5:18]
Khan Academy
Khan Academy: Geometry: Angle Bisector Theorem Proof
Explanation and proof of angle bisector theorem. [8:35]
Khan Academy
Khan Academy: Geometry: Point Line Distance and Angle Bisectors
Proof that a point on the angle bisector is equidistant from each side of the angle and proof that a point that is equidistant from each side of the angle lies on the angle bisector. [10:57]
Khan Academy
Khan Academy: Geometry: Triangle Area Proofs
Proof that the area of any triangle is half the product of the base and the height. Three different types of triangles are used to prove the formula. [10:23]
Khan Academy
Khan Academy: Geometry: Congruent Triangle Example 2
Demonstrates how to use triangle congruency to prove that corresponding sides of congruent triangles are congruent and then identifies other congruent parts in the overlapping triangle diagram. The proof is written in the form of a...
Khan Academy
Khan Academy: Geometry: Triangle Medians and Centroids
This video tutorial [8:59] reviews the definitions of median and centroid in relation to a triangle and proves that the centroid is two-thirds the way along a median. The proof is done be drawing a triangle in three-dimensions.
Khan Academy
Khan Academy: Geometry: Inscribed and Central Angles
Proof that the measure of an inscribed angle is half the measure of a central angle when the angles intercept the same arc. [14:16]
Massachusetts Institute of Technology
Mit: Blossoms: The Pythagorean Theorem: Geometry's Most Elegant Theorem
Use this video to help teach the Pythagorean Theorem. The video can be downloaded, there is a transcript of the video, and a teacher's guide to aid in using the video. [21:38]
Sophia Learning
Sophia: Proof (Harder)
This geometry resource discusses two types of proof. Video lessons demonstrating a flow proof and a two-column proof are included.
Sophia Learning
Sophia: Types of Proofs
Explore the similarities and differences between paragraph proofs, flow chart proofs, and two-column proofs. Assess learning with a quiz.
Sophia Learning
Sophia: Introduction to Geometric Proof
Explore the structure and how to complete a flow proof and a two-column proof.
Sophia Learning
Sophia: Intermediate Proof
Use the two-column proof and the flow proof to prove two triangles congruent.
Sophia Learning
Sophia: Language of Geometry
This video tutorial introduces some common terms for geometry including axiom, postulate, theorem, and corollary. Students can check their understanding with an assessment.
Khan Academy
Khan Academy: Geometry: Part 2 of the Proof of Heron's Formula
Completes the proof of Heron's formula that was begun in the video, "Part 1 of Proof of Heron's Formula." [12:08]
Khan Academy
Khan Academy: Geometry: Euler's Line Proof
Proves that the circumcenter, orthocenter, and centroid all lie on the same line, the Euler line. Proof relies on understanding of properties of similar triangles and properties of special parts of a triangle. [9:50]
Khan Academy
Khan Academy: Worked Examples: Geometry: Ca Geometry: Similar Triangles 1
In this video tutorial students explore a proof using similar triangles.
Khan Academy
Khan Academy: Triangles: Another Pythagorean Theorem Proof
Students explore the Pythagorean Theorem by exploring a visual proof of the Theorem as they watch a video tutorial.
Khan Academy
Khan Academy: Triangles: Fill in the Blank Triangle Proofs Example 1
In this video, we listen to how a geometry exercise is completed as the presenter demonstrates the reasoning behind proving that the corresponding parts of triangles are congruent. [9:42]
Sophia Learning
Sophia: Language of Geometry
This video lesson defines and provides an example of common geometry terms including theorem, postulate, axiom, and corollary.
Khan Academy
Khan Academy: Geometry: Inradius Perimeter and Area
Proof that the area of a triangle is equal to half the inradius times the perimeter of the triangle, or the area is equal to the inradius times the semiperimeter. This video also appears in the Geometry: Circles strand. [7:29]
Khan Academy
Khan Academy: Geometry: Exploring Medial Triangles
This video tutorial [11:32] explains what a medial triangle is and proves that the medial triangle divides the original triangle into four congruent triangles. Proof uses triangle similarity and triangle congruence postulates.
Other popular searches
- Geometry Proofs Worksheets
- Coordinate Geometry Proofs
- Basic Geometry Proofs
- Lesson on Geometry Proofs
- Proofs Geometry
- Geometry Proofs Polygon
- Geometry Proofs and Axioms
- Geometry Proofs Squares
- Geometry Proofs Angles
- Geometry Proofs + Square
- Euclidean Geometry Proofs
- Indirect Proofs Geometry