Instructional Video4:46
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What is the Formula for the Area of a Parallelogram?

5th - 8th
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.
Instructional Video0:07
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How Do You Figure Out Whether a Percent of Change is an Increase or a Decrease?

6th - 8th
Another word problem to figure out. Well, first off you are trying to figure out the percent of something and this means your formula will be a proportional equivalent. Once you have the known terms in the correct places you can figure...
Instructional Video5:14
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Where Does the Formula for a Term in an Arithmetic Sequence Come From?

10th - 12th
There is a formula to find the nth term in an arithematic sequence. But first, the instructor in the video will go through several steps and lots of explanations about how to get that formula. Watch and listen carefully. And then maybe,...
Instructional Video7:08
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What is Exponential Growth?

8th - 11th
Exponential functions often involve the rate of increase or decrease of something. When it's a rate of increase, you have an exponential growth function! The instructor discusses exponential function and how to determine if a value makes...
Instructional Video4:47
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How Do You Use the Formula for the Product of a Sum and a Difference?

8th - 9th
Multiply two binomials that have the same terms but different signs. One way is to FOIL it and then combine like terms. Another, shorter way to do it is to use a formula. There's a formula for the product of a sum and a difference. Using...
Instructional Video5:42
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What is the Formula for the Volume of a Pyramid?

6th - 12th
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...
Instructional Video4:36
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How Do You Find the Volume of a Sphere?

8th - 11th
The formula for the volume of a sphere is volume equals four-thirds pi times the radius cubed. That's a mouth-full. But if you are given the radius value of the sphere, all you have to do is plug it in and do the arithmetic. Just...
Instructional Video7:45
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How Do You Find the Lateral and Surface Areas of a Triangular Prism?

9th - 11th
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...
Instructional Video3:15
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How Do You Find the Surface Area of a Sphere?

6th - 12th
What do a basketball, a bowling ball, and a ping pong ball all have in common? They are spheres. So how do you measure the surface area of a sphere? Yes, there is a formula and all you have to do is know one measurement of the sphere to...
Instructional Video5:18
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How Do You Find the Lateral and Surface Areas of a Regular Pyramid?

9th - 10th
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....
Instructional Video6:25
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How Do You Find the Lateral and Surface Areas of a Rectangular Prism?

6th - 12th
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...
Instructional Video6:08
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How Do You Find the Lateral and Surface Areas of a Cylinder?

9th - 11th
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,...
Instructional Video5:37
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How Do You Find the Width of a Rectangle if You Know its Length and Perimeter?

6th - 9th
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.
Instructional Video4:45
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What is the Formula for the Area of a Triangle?

6th - 10th
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...
Instructional Video6:09
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How Do You Find the Height of a Triangle if You Know the Area and Base?

6th - 10th
Use the formula for the area of a triangle to find the height of the triangle. If the problem gives the value of the area and the value of the base, then the height can be found using the formula for the area of a triangle. The...
Instructional Video6:54
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How Do You Find the Height of a Trapezoid if You Know the Area and Bases?

5th - 8th
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....
Instructional Video4:08
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How Do You Find the Base of a Parallelogram if You Know the Area and Height?

6th - 10th
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...
Instructional Video4:38
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How Do You Find the Area of a Parallelogram?

6th - 8th
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.
Instructional Video5:36
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What is the Formula for the Area of a Sector of a Circle?

9th - 12th
Are you looking for the formula for the area of a sector of a circle? But what's a sector? A sector is just a fraction of the area of a circle. Follow the instructor as she illustrates and labels the different parts of a circle. She also...
Instructional Video3:19
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How Do You Find the Area of a Circle if You Know the Radius?

6th - 8th
There are basically two things you need to know to find the area of a circle. First, you need to use the correct formula. Second, you have to know the value of the radius. If you know these two things then all you have to do is plug the...
Instructional Video3:55
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How Do You Figure Out the Price of a Marked Up Item?

6th - 9th
Inflation and higher fuel costs means airplane tickets will cost more to the consumer. So here is a word problem that presents a real-world situation. Figure out the total price for an airplane ticket that has increased by 30% from the...
Instructional Video2:24
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How Do You Figure Out the Time Traveled if You Know Distance and Speed?

6th - 9th
Yes, it's a word problem, but you know the formula for distance, d=rt. The word problem here gives you two values so all you have to do is plug them into the correct place and solve. Don't forget to use the division property of equality...
Instructional Video4:12
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How Do You Find a Missing Angle in a Quadrilateral?

6th - 10th
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....
Instructional Video4:29
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How Do You Find a Missing Side of a Right Triangle Using Sine?

6th - 11th
What's a trigonometric ratio? It is a ratio between two sides of a right triangle. In this problem, find sin(A) in the given right triangle. Use the ratio of the opposite side divided by the hypotenuse to find sin(A). The instructor...