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Using indirect measurement, this video shows viewers how to find the height of a flagpole. The lecturer employs drawings as well as proportions to solve this problem, explaining each step. A useful resource to aid struggling learners and...

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### We found 178 resources with the concept right angles

Lesson Planet: Curated OER

#### What are Perpendicular Lines?

Perpendicular lines intersect to form right angles - four of them to be exact. Vertical angles, congruent angles, 90 degrees each, these are some of the special properties of perpendicular lines. Watch this video to find out a couple...

Lesson Planet: Curated OER

#### What are Complementary Angles?

Supplementary, obtuse, acute, complementary angles. It's good to know what all of these mean, but let's focus on one at a time. Complementary angles always add up to 90 degrees. So if given one angle in a complementary angle problem, the...

Lesson Planet: Curated OER

#### What is a Cone?

What are the things that make a shape a cone? Here's a list of things that define a cone: base, height, vertex, radius, curved side. Are you familiar with all these terms? The teacher diagrams a cone and identifies all the components in...

Lesson Planet: Curated OER

#### How Do You Determine if a Triangle Is a Right Triangle if You Know its Sides?

Use the Pythagorean Theorem formula to check if this given triangle, with the given lengths of each side, is a right triangle. It's as simple as plugging the given values into the formula and doing the math to see if the solution checks...

Lesson Planet: Curated OER

#### How Do You Solve a Problem Using Indirect Measurement with Shadows?

Using indirect measurement, this video shows viewers how to find the height of a flagpole. The lecturer employs drawings as well as proportions to solve this problem, explaining each step. A useful resource to aid struggling learners and...

Lesson Planet: Curated OER

#### Are These Right?

Is that a right triangle or a wrong triangle? Young mathematicians look at eleven different shapes and use a measuring tool of their choice to determine which triangles have right angles. Consider cutting out sets of the shapes to...

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#### How Do You Solve a Problem Using Indirect Measurement with Shadows?

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#### How Do You Find the Area of a Trapezoid?

Trapezoids can be tricky. Break down the process of finding the area of a trapezoid with this video! Viewers are given information about the area formula and shown exactly how to plug in information, solve, and simplify. This is a...

Lesson Planet: Curated OER

#### How Was the Distance Formula Derived?

Are you working on the distance formula? Derive the distance formula and help your learners by showing them the logic behind the distance formula. This practical video should help conceptual understanding and is appropriate for in-class...

Lesson Planet: Curated OER

#### Using a Protractor

Learn how to measure acute, right, and obtuse angles with a protractor. After reviewing the way the protractor works, fourth graders measure nine angles on their own. For extra practice, have them measure different angles in their...

Lesson Planet: Curated OER

#### Properties of Polygons, Parallel Sides, and Right Angles

Have fun with shapes! Third graders read a set of instructions and circle the shape in the description. They work on recognizing parallel sides and right sides. Use this resource as homework after your geometry lesson.

Lesson Planet: Curated OER

#### Drawing Angles

Get out those protractors! Once geometers can identify obtuse, acute, right, and straight angles, get them to measure and draw their own. There are six boxes here, each with an angle measurement. Learners use a protractor to draw the...

Lesson Planet: Curated OER

#### Square Corners

Are these angles greater than, less than, or equal to a square corner? Using a visual guide, young geometers label 16 angles into one of these three categories. Use this before introducing the terms acute, obtuse, and right angle, but...

Lesson Planet: Curated OER

#### Sorting 2-Dimensional Shapes

Some shapes have square corners, and some do not. Scholars participate in a sorting activity as they determine if these 12 shapes have square corners, categorizing them based on this attribute. Encourage geometers to draw the square into...

Lesson Planet: Curated OER

#### Acute and Obtuse Angles

Take a look at these angles: What kind are they? Give mathematicians practice identifying obtuse, acute, and right angles in this categorizing activity. Each type is pictured and explained at the top, and scholars examine nine sample...

Lesson Planet: Curated OER

#### Lines and Angles with K'NEX

Here is a geometry lessonwhich invites learners to create models using their knowledge of lines, segments, rays, and angles. This lesson reinforces geometric vocabulary and concepts through practical application, it also includes...

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#### Complementary Angles

Elementary schoolers find the missing angle in a complementary angle. This two-page worksheet contains six problems. Answers are provided.

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#### Unit 5 Section 2: Measuring Angles

An interactive assignment displays two example angles to teach how to measure them. When you click on the angles, a protractor appears! As practice, learners view a set of angles, estimate the size of each, and then enter the degrees in...

Lesson Planet: Curated OER

#### Angles

Learners identify obtuse and acute angles in comparsion to a right angle. They identify obtuse, acute, and right angles. Pupils use "Shape Measure" to construct obtuse, acute, and right angles. They review line segements to locate right...

Lesson Planet: Curated OER

#### Lines, Line Segments, Rays, and Angles - Practice 15.1

Is it a line, line segment, ray, or angle? Identifying geometric figures is the focus. In addition to identification, learners recognize right angles or tell if an angle is less than or greater than a right angle. They tell if lines are...

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#### Measuring Angles - Pretest Questions

Upper graders solve ten multiple choice problems about angles and measuring angles.

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#### Rays and Angles - Homework 16.2

Learners name seven different angles in three different ways and then classify each angle as acute, obtuse, right or straight. They solve one word problem.

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#### Year 5 Unit 2b

This slide-show is packed with information relating to a variety of mathematical concepts. Intended as an accompaniment to a full unit, this resource provides definitions, explanations, and opportunities for learners to practice their...

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#### Identify and Label Different Types of Angles

Students identify and label acute, obtuse, and right angles within a picture. Using Kid Pix software and digital photos, they manipulate, identify, and label the angles and describe the angles to a classmate.