Sesame Street
Jack Black and the Octagon
Jack Black describes an octagon. He finds everyday figures, like a stop sign, to describe the attributes of this shape. It is a great way to launch a discussion of geometric Math .
Curated OER
Area of a Trapezoid
Find the area of a trapezoid. The instructor goes through a discussion of defining a trapezoid, the ways to identify the height and base, and then calculates the area of the trapezoid. This visual exploration should solidify this concept...
Corbett Maths
Angles in Polygons
Learn to look at polygons from the right angle. Scholars first use the formula (n - 2) * 180 to determine the sum of the interior angles of a polygon. The video then asks them to consider the sum of the exterior angles.
Curated OER
What is the Formula for the Area of a Parallelogram?
So you are trying to tell me that a parallelogram is a rectangle in disguise? Wow! And I can use a similar formula of the area of a rectangle to find the area of a parallelogram? Wow! Ok, show me how! A=bh. So simple really.
Curated OER
How Do You Find the Square Root of a Perfect Square?
What is the relationship between squaring a number and taking the square root of a number? The instructor in the video explains the relationship of perfect square and its square root integer.
Curated OER
What is the Formula for the Volume of a Pyramid?
There are a lot of moving parts in this problem. There's the formula for a triangular prism. Then there's the formula for a triangular pyramid. And don't forget the formula for the area of the base of a triangular shape. Get out your...
Curated OER
How Do You Find the Lateral and Surface Areas of a Triangular Prism?
There are several pieces to this problem. But luckily all the necessary pieces are here. There are five variables and three different formulas to use to get the solutions. The instructor diagrams the triangular prism and labels the...
Curated OER
How Do You Find the Lateral and Surface Areas of a Regular Pyramid?
A regular pyramid has four equal triangular shaped sides and a square base. The lateral area is comprised of the area of the four triangular sides. The surface area is the area of the four triangular sides plus the area of the base....
Curated OER
How Do You Find the Lateral and Surface Areas of a Rectangular Prism?
What are lateral faces? How do you find the area of all the lateral faces? What to do with the perimeter of the base? Then what do you do with those values? You use it to help determine the total lateral area of a rectangle. Yes, more...
Curated OER
How Do You Find the Lateral and Surface Areas of a Cylinder?
There are three formulas that need to be used to solve this problem. The formula for the lateral area of a cylinder, the formula for the circular base of the cylinder, and then the formula for the surface area. It seems like quite a bit,...
Curated OER
How Do You Find the Width of a Rectangle if You Know its Length and Perimeter?
Use the formula for the perimeter of a rectangle to find the value of the width. Plug the given values of the perimeter and the length into the formula and solve. It is as easy as it looks.
Curated OER
What is the Formula for the Area of a Triangle?
The teacher explains how the formula for a triangle was determined. It is related to a parallelogram. What? The formula for the area of a triangle is derived from the area of a parallelogram? Seeing is believing, so watch this video to...
Curated OER
What is the Formula for the Area of a Trapezoid?
Make a parallelogram out of two trapezoids to find the area of one trapezoid? Sounds pretty complicated. Well, it's not complicated but there are a lot of steps. The instructor does a pretty good job of diagramming and explaining just...
Curated OER
How Do You Find the Height of a Trapezoid if You Know the Area and Bases?
Find the height of a trapezoid given the values of the two bases and the area. First write out the formula for the area of a trapezoid. Then identify all the variables and match up the given values. Now plug the values into the formula....
Curated OER
How Do You Find the Base of a Parallelogram if You Know the Area and Height?
There are three variables in the formula for a parallelogram. Two of the values are given in this problem. Find the third value. Identify what each of the variables means. Match up the given values to the variables. Then solve for the...
Curated OER
How Do You Find the Area of a Parallelogram?
So you are trying to tell me that a parallelogram is a rectangle in disguise? Wow! And I can use a similar formula of the area of a rectangle to find the area of a parallelogram? Wow! Ok, show me how! A=bh. So simple really.
Curated OER
What is the Formula for the Area of a Circle?
Cut up a circle and make a parallelogram! What? No way! Yes way! Watch the instructor illustrate just how to cut up the circle and get that parallelogram to then get the formula for the area of a circle. It really works! Base,...
Curated OER
How Do You Find a Missing Angle in a Quadrilateral?
Oh no, there is a missing angle in a quadrilateral. Where did it go? It didn't go anywhere, it's just missing the value of the angle. So how do you find that missing value? Use a formula of course. Everything in algebra uses a formula....
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's the Power of a Quotient Rule?
What's the definition of the power of a quotient rule? You have a fraction that has variables and exponents in the numerator and the denominator, and the whole thing is to a power. Oh my! Don't cry! You can do this. Once you see the rule...