Indirect proof Teacher Resources

Find Indirect proof lesson plans and worksheets
Showing 1 - 24 of 128 resources
Lesson Planet

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...
3:39
Lesson Planet

Indirect Proofs in Algebra and Geometry: Lesson

For Students 7th - 12th
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.
Lesson Planet

Sum of Rational and Irrational is Irrational

For Teachers 8th - 9th Standards
Sometimes the indirect path is best. Scholars determine whether the sum of a rational number and an irrational number is irrational. Reading a transcript of a conversation between classmates leads to an indirect proof of this concept.
Lesson Planet

Indirect Proof and Inequalities in One Triangle

For Teachers 10th
In this geometry worksheet, 10th graders order the sides and angles of a triangle and determine the range of the third side of a triangle given the lengths of two sides.  The one page worksheet contains sixteen questions.  Answers are...
Lesson Planet

Special Segments in Triangles

For Students 10th
In this special segments in triangles activity, 10th graders solve 86 various types of problems that include determining the measure of various triangles. They draw and label a figure that illustrates each situation. Then, students prove...
Lesson Planet

Conditional Statements

For Teachers 9th - 12th
Young scholars are introduced to the topic of proofs in Geometry. During a PowerPoint presentation, they take notes on indirect proofs and have groups of students write a true statement. They are assessed on the statement and how well...
4:19
Lesson Planet

Indirect Measurement: Lesson

For Students 7th - 11th Standards
When the tape measure will not reach, use similarity. An installment of a large playlist on geometry introduces the method of indirect measurement. Using a story of finding the distance to the sun, the video shows how to use similar...
4:01
Lesson Planet

Classifying Parallelograms: Lesson

For Students 8th - 11th Standards
Properly organize parallelograms. Given special parallelograms, the narrator of a short video explains the properties of each. The section of a playlist on geometry uses the properties to classify the special parallelograms.
3:01
Lesson Planet

Isosceles Triangles: Lesson

For Students 8th - 11th Standards
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.
3:02
Lesson Planet

Equilateral Triangles: Lesson

For Students 8th - 11th Standards
Take a second look at triangles that are equal all the way around. The video reminds viewers what an equilateral triangle is and points out that the three angles are the same. Using the fact that equilateral triangles are also isosceles,...
3:41
Lesson Planet

Parallelograms: Lesson

For Students 8th - 11th Standards
Properties spawn from parallel sides. With the aid of diagrams, the presentation shows the different properties of parallelograms. The segment of an extensive geometry playlist lists the properties that using the parallel sides of a...
3:10
Lesson Planet

Tangent Lines: Lesson

For Students 8th - 11th Standards
Point out properties of a line tangent to a circle. The resource provides two theorems dealing with tangent lines to a circle. A section of a geometry playlist uses the relationship between a radius and a tangent line to find missing...
4:18
Lesson Planet

Measuring Distances: Lesson

For Students 5th - 8th Standards
Let's rule the coordinate plane. By reviewing the marking on rulers, the video discusses how to determine the measurement between two points. The resource, a portion of a basic geometry playlist, determines the length of a side of a...
4:44
Lesson Planet

Measuring Angles: Lesson

For Students 4th - 6th Standards
Develop a degree of measurement. With the aid of a protractor, the video shows how to measure angles. The segment of a larger playlist on geometry basics points out that it is possible to start at a value other than zero when measuring...
3:02
Lesson Planet

Classifying Angles: Lesson

For Students 4th - 8th Standards
It's time to put the angles in place. Using diagrams, the video presents the basic definitions of the four classifications of angles. The segment in an informative playlist on basic geometry also provides informal descriptions of the...
3:00
Lesson Planet

Complementary Angles: Lesson

For Students 6th - 10th Standards
Complement the angle definition. The resource, a video within a basic geometry playlist, introduces the definition of complementary angles. Using the definition, the presentation finds complements of given angles.
2:17
Lesson Planet

Linear Pairs: Lesson

For Students 6th - 10th Standards
Place angles in a line. Part of a playlist on basic geometry, an informative video teaches pupils the definition of a linear pair and how to identify them. Using their properties, the resource demonstrates how to solve problems involving...
2:55
Lesson Planet

Supplementary Angles: Lesson

For Students 6th - 10th Standards
Supplement your knowledge of angles. Part of a playlist exploring geometry concepts, an interesting video introduces the definition of supplementary angles. Using the definition, the presentation shows how to find the supplement to a...
2:51
Lesson Planet

Vertical Angles: Lesson

For Students 6th - 10th Standards
Define angles across from each other. An informative segment from a larger playlist on geometry introduces vertical angles and shows they have equal measures. Using their properties, the presenter solves problems involving vertical angles.
4:55
Lesson Planet

Classifying Triangles: Lesson

For Students 4th - 8th Standards
That's correct, it is right and scalene. The video introduces the two methods for classifying triangles, sides, and angles. A resource in the playlist for basic geometry provides the definitions for each of the classifications.
4:00
Lesson Planet

Classifying Polygons: Lesson

For Students 4th - 8th Standards
For your eyes only: classify the names of polygons. After providing the definition of a polygon, the video introduces the two major classifications of polygons, concave and convex. The segment of a larger playlist on geometry continues...
4:35
Lesson Planet

Inductive Reasoning: Lesson

For Students 6th - 12th
Let's get specific about the general conclusion. The video, a portion of an extensive geometry playlist, introduces inductive reasoning. Using patterns, the resource explains how inductive reasoning goes from the specific to general.
5:47
Lesson Planet

Deductive Reasoning: Lesson

For Students 6th - 12th
It is elementary, my dear Watson. A segment in a playlist on geometry introduces the idea of deductive reasoning. The video goes over three rules that apply to deductive reasoning and conditional statements.
1:57
Lesson Planet

Alternate Interior Angles: Lesson

For Students 9th - 12th Standards
Concepts of alternate interior angles parallel the concepts of corresponding angles. Using a diagram, the presentation defines and identifies alternate interior angles formed by a transversal and two parallel lines. The video in a...

Browse by Subject


Indirect proof