CK-12 Foundation
Proportions with Angle Bisectors: Lesson
Half at one end becomes proportional on the other. As part of a basic geometry playlist, the video introduces the Angle Bisector Theorem. The presentation uses the theorem to find missing lengths in triangles.
CK-12 Foundation
SAS Similarity Theorem: Lesson
When given two sides and an angle, make similar triangles. The video describes the SAS Similarity Theorem. Using the theorem, the segment of a larger geometry playlist determines whether two triangles are similar.
CK-12 Foundation
The Third Angle Theorem: Lesson
If two sets of angles are equal, the third set is too. An informative portion of a playlist on geometry develops the Third Angle Theorem for triangles. Using the theorem, the presenter shows how to determine the measure of missing angles...
CK-12 Foundation
Using Ratios: Lesson
How do ratios work in geometry? The video answers just this question in order to help your class master an important skill. Using the concept of ratios, this segment in an extensive geometry playlist applies ratio reasoning to...
CK-12 Foundation
Trapezoids: Lesson
Using the definition of a trapezoid, the segment within a large playlist on basic geometry explains other properties of trapezoids. The video introduces the special properties held by isosceles trapezoids.
CK-12 Foundation
Proving a Quadrilateral Is a Parallelogram: Lesson
If it has the properties of a parallelogram, it must be a parallelogram. A segment of a playlist on geometry presents the converses of the properties of a parallelogram. Given a quadrilateral with specific characteristics, the video...
CK-12 Foundation
Exterior Angles in Convex Polygons: Lesson
Going around is the same no matter the number of sides. An installment in a geometry playlist explains exterior angles of a convex polygon. The video presents the formula to find the sum of the angles along with the formula for finding...
CK-12 Foundation
Indirect Proofs in Algebra and Geometry: Lesson
Indirectly, it is a good proof method. A segment of a playlist on geometry introduces a way to prove geometric and algebraic statements. Using a general examples, the video shows how to develop an indirect proof.
CK-12 Foundation
Angle Bisectors: Lesson
Apply bisectors and distances to angles. Using the definition of an angle bisector, a portion of a geometry playlist draws a diagram showing the angle bisector. The video details properties of an angle bisector and their converses....
CK-12 Foundation
Midsegment Theorem: Lesson
Use half the length to connect the midpoints. A section of a playlist on geometry introduces the concept of a midsegment of a triangle and how to find it. The video states the properties of the midsegment which make up the Midsegment...
CK-12 Foundation
Isosceles Triangles: Lesson
Two sides give us two angles. A segment of a playlist on basic geometry revisits isosceles triangles. The presentation explains several properties and theorems related to isosceles triangles.
CK-12 Foundation
SAS Triangle Congruence: Lesson
SAS is not just a spy organization. A section of an extensive geometry playlist introduces a way to show two triangles are congruent, SAS. Using diagrams, the video provides an explanation by showing only one triangle is formed with two...
CK-12 Foundation
Creating Congruence Statements: Lesson
Provide a large amount of information in a short statement. A segment of a playlist on basic geometry introduces the notation to denote congruence between two figures. The video shows how to read corresponding parts from a congruence...
CK-12 Foundation
Congruent Triangles: Lesson
Given two congruent triangles, the resource provides the definition of congruent triangles and marks the corresponding parts. The portion of a basic geometry playlist shows the triangles are congruent by moving one on top of the other...
CK-12 Foundation
Exterior Angles Theorems: Lesson
Use the inside to find the outside. The resource presents two theorems dealing with exterior angles of a triangle. Using the two theorems, the segment from a larger geometry playlist works problems to solve for angle measures.
CK-12 Foundation
Triangle Sum Theorem: Lesson
The measures all add up. The presentation, part of a helpful playlist on geometry, provides the statement of the Triangle Sum Theorem. Using the theorem, the video shows how to find the missing measure of an angle.
CK-12 Foundation
Distance Between Parallel Lines: Lesson
Rely on slope when counting won't do. Using horizontal and vertical parallel lines, the presentation shows scholars how to find the distance by counting. The video uses the relationship of the slopes of perpendicular lines to find two...
CK-12 Foundation
Finding the Distance Between Two Points: Lesson
Point out an application of Pythagoras. The segment of an essential playlist on geometry provides a quick review of the Pythagorean Theorem. Using a right triangle to show the positions of two points, the presenter calculates the...
CK-12 Foundation
Perpendicular Lines in the Coordinate Planes: Lesson
Get the slope right with two easy steps. By placing two perpendicular lines on the coordinate plane, the video determines the relationship of the slopes of the two line lines. The resource is a part of an informative and extensive...
CK-12 Foundation
Parallel Lines in the Coordinate Plane: Lesson
Discover the parallel structure of parallel lines. Provided with two parallel lines on a coordinate plane, the presenter shows that the rise and run, or slope, of the two lines are the same. The resource, which is a portion of a larger...
CK-12 Foundation
Congruent Angles and Bisectors: Lesson
How is congruence shown? Using angles, the resource introduces the congruence symbol and explains the meaning of being congruent. A segment of a larger playlist on basic geometry discusses bisection as a way to arrive at two congruent...
CK-12 Foundation
Slope in the Coordinate Plane: Lesson
Rise and run to find slope. Given a graph of a line, the presentation shows how to find the slope by determining the rise and the run. The resource, part of an extensive geometry playlist, reveals the four basic slopes of lines.
CK-12 Foundation
Same Side Interior Angles: Lesson
Supplement your scholars' knowledge of angles involved with parallel lines. Using the properties of alternate interior angles and linear pairs, the presenter shows interior angles located on the same side of a transversal of parallel...
CK-12 Foundation
Alternate Exterior Angles: Lesson
Use an alternate approach to parallel lines. A resource in a comprehensive playlist on basic geometry develops the concept of alternate exterior angles and parallel lines. The presentation demonstrates how to identify alternate exterior...