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215 resources with the concept right angles

2:12
Lesson Planet

What are the Legs and Hypotenuse of a Right Triangle?

For Teachers 6th - 10th
What are all the parts of a right triangle called? What makes it a right triangle? Legs? Triangles have legs? Hypotenuse? Pythagorean Theorem? The instructor diagrams and identifies all the parts of a right triangle for you.
3:34
Lesson Planet

How Do You Find the Area of a Triangle?

For Teachers 6th - 8th
The formula for the area of a triangle is: area equals one half the base times the height. If you have been given these two values then all you need to do is plug them into the formula and solve. Don't forget to write the correct ending...
1 In 1 Collection 4:19
Lesson Planet

How Do You Find the Area of a Trapezoid?

For Teachers 7th - 9th
Trapezoids can be tricky! Break down the process of finding the area of a trapezoid with an engaging math video. Learners explore area formula and shown exactly how to plug in information, solve, and simplify. 
5:22
Lesson Planet

What are Perpendicular Lines?

For Teachers 6th - 10th
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...
3:20
Lesson Planet

What are Complementary Angles?

For Teachers 6th - 10th
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...
2:44
Lesson Planet

What is a Cone?

For Teachers 6th - 11th
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...
2:49
Lesson Planet

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

For Teachers 6th - 10th
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...
7:15
Lesson Planet

Engineering an Empire - Greece, Part 3/5

For Teachers 6th - 12th
How do you ensure a steady supply of drinking water to a city in the dry, arid, Mediterranean Climate? How do you get water from the spring located on the other side of a mountain to your city? If you start from both sides of the...
4:22
Lesson Planet

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

For Teachers 6th - 10th
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

Are These Right?

For Teachers 3rd - 5th Standards
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...
4:57
Lesson Planet

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

For Teachers 6th - 12th
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...
4:55
Lesson Planet

How Do You Find the Area of a Trapezoid?

For Teachers 6th - 12th
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...
1 In 1 Collection 4:54
Lesson Planet

How Was the Distance Formula Derived?

For Teachers 6th - 12th
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...
1 In 1 Collection
Lesson Planet

Using a Protractor

For Students 3rd - 5th Standards
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...
1 In 1 Collection
Lesson Planet

Properties of Polygons, Parallel Sides, and Right Angles

For Students 2nd - 4th Standards
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

Drawing Angles

For Students 4th - 5th
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

Square Corners

For Students 2nd - 4th Standards
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

Sorting 2-Dimensional Shapes

For Students 2nd - 4th Standards
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

Acute and Obtuse Angles

For Students 4th - 5th Standards
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

Lines and Angles with K'NEX

For Teachers 6th - 8th
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...
Lesson Planet

Measure, Draw, and Classify Angles - Reteach 14.4

For Students 4th - 6th Standards
Learners use a protractor to draw, measure, and classify angles. They solve six problems total. Note that the angles all come from a set of three intersecting lines, making this ideal as an enrichment for those who are beyond...
Lesson Planet

Lines, Line Segments, Rays and Angles - Homework 15.1

For Students 4th - 5th
Here is an identifying lines, line segments, rays, and angles activity which has learners identify the figures by telling whether figures are right angles, less than a right angle, or greater than a right angle, identifying lines as...
Lesson Planet

Complementary Angles

For Students 4th - 6th
Elementary schoolers find the missing angle in a complementary angle.  This two-page worksheet contains six problems. Answers are provided.
Lesson Planet

Unit 5 Section 2: Measuring Angles

For Students 4th - 6th Standards
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...