Curated OER
What is a Polygon?
What makes a figure a polygon? Does it have three or more sides? Is it a closed figure? If the answer is yes to both of those questions then it's a polygon. But wait! Some of these polygons have special names based on the number of sides...
Curated OER
How Do You Find the Sum of the Interior Angles of a Polygon?
Squares, pentagons, triangles, polygons. How is it possible to figure out the sum of the interior angles of any of these multi-faceted shapes? There's got to be a formula. Of course there's a formula. That's what algebra is all about,...
Curated OER
How Do You Find Measures of Missing Exterior Angles?
The sum of the exterior angles of any polygon is always 360 degrees. So knowing this, finding missing exterior angles can be done as long as there is only one variable in the equation. All that needs to be done is to add all the known...
Curated OER
How Do You Find the Measures of Exterior Angles of a Polygon if You Know the Interior Angles?
What are the exterior angles of a polygon? Polygons have exterior angles? How? Oh, extend all the lines, and find the value of each of the supplementary angles. No problem as long as one knows what supplementary angles means. Not sure?...
Curated OER
What Does Congruent Mean?
Two figures are congruent if they have the same size and shape. Line segments can also be congruent if they are of the same length. Vertical angles created by intersecting lines are always congruent. Polygons that have matching angles...
Curated OER
What is a Rhombus?
A closed figure with four sides means it's a quadrilateral. Each of the different types of quadrilaterals have special properties. The instructor in this video explains the special properties of a rhombus. Parallel sides and congruent...
Curated OER
What is a Regular Polygon?
What makes a polygon a regular polygon? Does this mean there are irregular polygons? For a polygon to be classified as a regular polygon, all the sides must be congruent and all the angles must be congruent. Those are the two rules that...
Curated OER
What is a Rectangle?
What are the characteristics and properties of a quadrilateral that make it a rectangle? Four sides? Right angles? Parallel sides? Watch this video and follow along as the instructor explains the terms and properties that make a...
Curated OER
What is a Quadrilateral?
What's so special about quadrilaterals? There are five special types, yes, five. Can you name them? The instructor in this video diagrams and illustrates the special types of quadrilaterals and explains what makes each one special.
Curated OER
What is a Pyramid?
One base, triangular sides, and defined polygons are all parts of what make up a pyramid. Check out this video and see the instructor draw pictures of a variety of pyramids. She identifies the specific parts and gives them names based on...
Curated OER
Types of Polygons - Geometry Help
If it has three sides it's a triangle! Learn about the different types of polygons and how they are classified by the number of sides they have. This clip clearly defines each type of polygon, but fails to show examples.
Curated OER
How Do You Classify Quadrilaterals?
A rectangle, a rhombus, a square, a trapezoid, and a parallelogram, are these quadrilaterals? What are the criteria that make and shape a quadrilateral? It has something to do with parallel sides, congruent sides, and congruent angles....
Sesame Street
Sesame Street: Cookies of the Caribbean
Yo-ho-yo-ho, it's a pirate's life for Cookie Monster. Follow Captain Snack Sparrow as he focuses on the task at hand to find Davie Jones' Cookie Jar. Along the way he has to understand clues and sort shapes and objects by their...
PBS
Pbs Learning Media: Peg + Cat: Geometry Collection
This collection includes 16 Peg + Cat video clips about geometry including 2-D and 3-D shapes.