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Instructional Video11:40
2
2
Flipped Math

Properties of Parallel Lines

For Students 9th - 12th Standards
Work within a parallel universe. Scholars learn about the relationships of angles when two parallel lines are intersected by a transversal. They see how to find the measurements of all eight angles by knowing the measure of one angle....
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Lesson Plan
Curated OER

Parallelism in Our Everyday World: Parallel Lines and Beyond

For Teachers 9th - 10th
Students broaden their outlook on geometry in their everyday environment. They explore the properties of parallel lines and parallelograms and discover ways to prove the existence of parallel lines and discuss the concept of parallel lines.
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Instructional Video9:36
2
2
Flipped Math

Proving Lines Parallel

For Students 9th - 12th Standards
Show it can all be proved. Scholars learn the converses of the properties of parallel lines. Using the converses, pupils determine which lines are parallel based on angle measurements and practice using a flow proof to show that two...
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Lesson Plan
Mathematics Assessment Project

Classifying Equations of Parallel and Perpendicular Lines

For Teachers 9th - 12th Standards
Parallel parking might be difficult, but finding parallel lines is fairly simple. In this lesson, learners first complete an assessment task involving parallel and perpendicular lines in the coordinate plane. Individuals then take part...
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Worksheet
Curated OER

Properties of Angles, Lines, and Triangles

For Students 10th
In this properties of angles, lines and triangles instructional activity, 10th graders solve and complete 28 different problems that include determining the measurement of various figures shown. First, they use the geometric properties...
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Lesson Plan
Curated OER

Constructing Parallel Lines

For Teachers 8th - 10th
Students construct parallel lines using a protractor and a straightedge. In this geometry lesson, students identify the properties of parallel lines. They use Cabri to graph and observe the lines.
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Lesson Plan
Illustrative Mathematics

Joining Two Midpoints of Sides of a Triangle

For Teachers 9th - 11th Standards
Without ever using the actual term, this exercise has the learner develop the key properties of the midsegment of a triangle. This task leads the class to discover a proof of similar triangles using the properties of parallel lines cut...
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Lesson Plan
Curated OER

Parallel and Perpendicular Lines

For Teachers 10th
Tenth graders explore parallel and perpendicular lines.  In this geometry lesson, 10th graders investigate the relationships associated with parallel lines and transversals, perpendicular lines, and the angles formed by these lines. ...
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Worksheet
Curated OER

Parallel and Perpendicular Lines

For Students 9th - 11th Standards
Young geometers get some solid skills practice in evaluating slopes. Beginning with the basics of slope through two points and progressing through properties of parallel and perpendicular lines, the building of skills is gradual and...
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Worksheet
Curated OER

Diagnostic Test: Angles & Parallel Lines

For Students 9th - 11th
In this diagnostic test worksheet, students solve problems involving angles, parallel lines, and perpendicular lines. They identify alternate interior angles, alternate exterior angles, and corresponding angles. Students find the...
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Lesson Plan
Curated OER

Determining Angle Measure with Parallel Lines

For Teachers 9th - 12th
Students observe and solve examples of corresponding angle postulates, alternate interior angle theorems, and exterior and consecutive angles. They complete the Determining Angle Measure With Parallel Lines worksheet.
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Lesson Plan
Curated OER

Lines, Lines, Everywhere

For Teachers 8th - 10th
Students explore linear equation suing real life scenarios. In this algebra instructional activity, students find the slope and intercept of a line. They create table of values to plot their graph and draw conclusions.
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Lesson Plan
EngageNY

Unknown Angle Proofs—Proofs of Known Facts

For Teachers 9th - 10th Standards
Lead the class in a Greek history activity with a geometric twist. Pupils relate a short video about geometric properties to modern-day methods of solving for unknown angles. They discuss parallel line theorems and complete practice...
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Assessment
Inside Mathematics

Quadrilaterals

For Teachers 9th - 12th Standards
What figure is formed by connecting the midpoints of the sides of a quadrilateral? The geometry assessment task has class members work through the process of determining the figure inscribed in a quadrilateral. Pupils use geometric...
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Assessment
Curated OER

Expressing Geometric Properties with Equations

For Students 9th - 11th Standards
Algebra and geometry are not interchangeable. Demonstrate why not with a series of problems that deal with the equations of circles and equations of lines that meet specific criteria. 
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Lesson Plan
Virginia Department of Education

Properties of Quadrilaterals

For Teachers 9th - 11th Standards
What type of quadrilateral is that? Discover the difference between the types of quadrilaterals. Small groups investigate types of quadrilaterals using geometry software to find their properties. To keep track of the different...
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Lesson Plan
Curated OER

Making Parallel Lines

For Teachers 8th - 10th
Students differentiate between parallel and perpendicular lines. In this geometry lesson plan, students make conjectures and apply it to solve real life situations. They collect data and make predictions based on the data.
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Worksheet
Curated OER

Skills and Application

For Students 9th - 10th
In this geometry activity, students identify the different properties of parallel lines cut by a transversal. They identify the different angles created by such lines. There are 16 questions.
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Worksheet
Curated OER

Parallel and Perpendicular Lines

For Students 9th - 10th
In this algebra/geometry activity, students investigate the slopes and equations of parallel and perpendicular lines.  The two page activity contains a combination of eleven multiple choice and free response questions.  Solutions are...
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Lesson Plan
Alabama Learning Exchange

Mirror, Mirror on the Wall: Reflections of Light

For Teachers 9th - 12th Standards
Why can we see our reflection in a window but not a brick wall? Young physicists learn the Law of Reflection and various light properties that help them answer this and other questions about reflection. Use the PowerPoint to introduce...
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Lesson Plan
2
2
Illustrative Mathematics

Are They Similar?

For Teachers 9th - 11th Standards
Learners separate things that just appear similar from those that are actually similar. A diagram of triangles is given, and then a variety of geometric characteristics changed and the similarity of the triangles analyzed. Because the...
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Unit Plan
1
1
Mathematics Vision Project

Similarity and Right Triangle Trigonometry

For Teachers 10th - 12th Standards
Starting with similar triangles and dilation factors, this unit quickly and thoroughly progresses into the world of right triangle features and trigonometric relationships. Presented in easy-to-attack modules with copious application...
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Lesson Plan
EngageNY

Special Lines in Triangles (part 1)

For Students 9th - 10th Standards
Allow your pupils to become the mathematicians! Individuals explore the properties of a midsegment of a triangle through construction and measurement. Once they figure out the properties, learners use them to draw conclusions.
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Lesson Plan
Key Curriculum Press

Properties of Special Parallelograms

For Teachers 9th - 11th Standards
Rhombuses, rectangles and squares are have special properties. In this lesson plan, young geometers investigate and make conjectures about diagonals, angles, and parallel lines of parallelograms.