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How To: Find measure of an exterior angle of a regular polygon

This tutorial the shows how to find out the measure of an exterior angle of a regular polygon. He shows the formula to find it which is 360/n, where n is the number of sides of the regular polygon. He goes on further to explain the formula by taking an 18-sided regular polygon as example and computes its exterior angle as 360/18, which is 20 degrees. If you are looking to compute the exterior angel of a regular polygon, follow the procedure given in this tutorial.

How To: Express a ratio as a fraction in simplest form

From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps. With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to rewrite a ratio as a fraction in its simplest form.

How To: Solve combination and permutation problem

Check out this instructional math video that demonstrates how to solve combination and permutation math problems. In the 16th lesson, learn how to solve SAT problems using the Official SAT Study Guide. Here are the math problems and their page numbers that this video covers:

How To: Convert fractions to percents in two steps

This video shows you how to easily convert fractions to percents. You can convert fractions to percents in 2 easy steps. The first step is multiplying the fraction by 100 (e.g.. your fraction is 3/5; 3/5 x 100 = 3/5 x 100/1 = 300/5). The second step is reducing the fraction, when possible (e.g.. 3/5 x 100/1 = 300/5 = 60). Don't forget to add the percent sign (%)(you obtained 60%). That's it! Good Luck!

How To: Find the opposite and absolute value of a number

View the absolute value of a number as its distance from zero. When you take the absolute value of a number, you always end up with a positive number (or zero). Whether the input was positive or negative (or zero), the output is always positive (or zero). For instance, | 3 | = 3, and | _3 | = 3 also. This property that both the positive and the negative become positive makes solving absolute-value equations a little tricky. But once you learn the "trick", they're not so bad. Let's start with ...

How To: Isolate a variable

If you're struggling a bit with algebra, check out this video to learn how to isolate a variable. Isolating a variable is a matter of separating and simplifying.

How To: Create elaborate drawings on a graphing calculator

Texas Instruments is one of the best known companies for creating graphing calculators. In this video tutorial you will see how to use a little known feature that lets you create pretty elaborate drawings on it. This is a great time-waster in math class! Who needs algebra or geography anyways? Art class is what you need, art class on a graphing calculator.

How To: Calculate Type I (Type 1) errors in statistics

Need a quick primer on how to solve type-1 error problem in stats? Let this video be your guide. From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps. For all of the details, watch this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials.

How To: Multiply Any Number by 11 with a Super Fast Mental Trick

Most of the time, when I’m bored during math class, I play with my calculator to satisfy my boredom. Recently, I've discovered that when multiplying any number by 11, 111, or any number similar to it, that it has a pattern (though I guess everything in math has a pattern). I don't know if this technique is original, because I didn't read anything about this. It's just mere observation. If it’s a tried and true technique, let me know.

How To: Simplify cube roots

In this video, the narrator presents the viewer with a quick, painless way of simplifying cube roots. The narrator presents many methods to simplify square roots to appeal to different learning styles. By doing things like dividing the power by the root to figure out the power of a number x, the viewer is better able to tackle square-rooting numbers that may not have friendly roots. The video gets more complex as it goes on, eventually teaching the viewer to split the inside of a root up if t...

How To: Find the coordinate of a point

In this video the author shows how to plot a point on the coordinate plane. He explains about the coordinate plane and shows how to read and write points to it with an example. He says that any point on the coordinate plane has an x, y- coordinate values. He says that for any point its projection on the x-axis is its x-coordinate and the points projection on y-axis is its y-coordinate. He shows how to find this out for a sample value and plots the coordinates of it. In this video the author u...

How To: Solve simple interest algebra problems

In this math lesson we will learn how to solve problems involving simple interest. When you deposit money in a savings account, the bank pays you interest at a certain rate called interest rate. There are two types of interest: simple interest and compound interest. In this lesson we will talk about simple interest. We will use the following important formula:

How To: Find a percentage of a whole number in basic math

Need help figuring out how to find a given percentage of a whole number (e.g., 16% of 736)? Watch this free video lesson. From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just finish your homework or study for that next big test). With this free math tutorial, you'll learn how to find percentage values in basic arit...

How To: Solve algebraic equations with the y = mx+b format

This video shows us how to solve algebraic equations with the y = mx+b format. When talking about solving y=mx+b format, it’s about solving linear equations so that y is on one side and with some terms x on the other side. Here in this equation 'm' is actually the slope of the line and slope= (rise/run) and it is interrupted with the term 'b'. This can be explained by taking an example of the same format. In the example 2x+3y=9, we need to shift the term '2x' to the other side so that the equ...

How To: Solve problems involving functions in algebra

Need to know how to solve function problems in algebra? From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just finish your homework or study for that next big test). With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to work with and solve functions.

How To: Calculate the area of complex shapes

Watch this video to learn how to calculate the area inside complex figures--shapes composed of multiple smaller, simpler shapes. The first step is to break the shape into its simpler component shapes. Then, using the information you have about the large shape, find all information you can about the smaller ones: base, height, etc. Next, find the areas of the smaller component shapes. Finally, add the areas of each of the component shapes together to find the area of the complex shape. Now you...

How To: Calculate the modulus and argument of a complex number

Need a little help with your math homework? No problem, the Math Centre offers students video tutorials that will provide as a reference guide for self-study. Students get self-study resources targeted to the needs of individual courses, and teachers gain generic mathematics support and study materials for use with students.

How To: Find the equation of a tangent line

This is the video about how to find the equation of a tangent line. As you may recall, a line which is tangent to a curve at a point a, must have the same slope as the curve. Therefore, the slope of the tangent is m = lim f(a + h) - f(a) h-->0 h Since the slope equation of the tangent line is exactly the same as the derivative definition, an easier way to find the tangent line is to differentiate using the rules on the function f. For example, Find the slope of a line tangent to the function ...

How To: Normalize a data set into another scale

Comparing evaluations of the same thing done on different scales can seem difficult, but there is a simple equation you can use to translate something expressed in one numerical scale into another. This video will show you how to use it and make your math life easier.

How To: Solve ratio problems

Check out this instructional math video that demonstrates how to solve ratio problems. In the 14th lesson, learn how to solve SAT problems using the Official SAT Study Guide. Here are the math problems and their page numbers that this video covers:

How To: Find the slope's unit of measure

This educational video from free math tutoring shows how to calculate the slope of a line and assign units to the answer obtained. This video assumes that the viewer is familiar with the concepts of axes and co-ordinate geometry. The narrator uses a commonly used formula to calculate the slope of the line in the first section of the video. In the second section, the narrator demonstrates how to assign units to the answer, as per the question asked.

How To: Multiply proper & improper fractions

So, you need a little extra help in the fractions department? No problem. In this two-part vieo tutorial, learn how to multiply proper fractions and mixed numbers in part one. In part two, learn how to multiply mixed numbers & multiply sets of improper fractions.

How To: Draw a translation in Geometry

In this tutorial, the instructor shows how to do a translation in geometry. Now he shows this by using various drawings and by practically explaining it while performing the translation. He first shows how to set up the translation line and now goes on to translate each and every vertex by drawing a parallel line to the translation line through each vertex, which is the same length as the length of the translation line. Now he combines the end points of the translated lines which gives us the...

How To: Solve permutation & combination word problems

From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just finish your homework or study for that next big test). With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to unpack and solve word problems invplving permutations and combinations in basic stati...

How To: Express a fraction in lowest terms in basic math

From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps. With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to write a fraction in its lowest terms.

How To: Determine if a point lies on a line in slope intercept

In this video the author shows how to find out if a Point lies on a Line in Slope Intercept Form. He shows it by an example where he takes a point, which is an ordered pair in the form (x, y) and a line, which is an first degree equation. Now he substitutes the values of x and y in the equation and checks if both the sides of the equation match. If it matches we can conclude that the point lies on the line. By following the method given in this tutorial you can find out if a given point lies ...

How To: Divide larger numbers and do long division

This is video for how to divide large numbers by doing long division with easy methods. This video describes that dividing the "Dividend" with "Divisor" to get the "Quotient" and "Remainder" if they exist. In the given example first "25" taken as the Dividend and "5" is will be the Divisor. Divide this value the multiplication is needed. For above example "5*5=25" is the result so, the "Quotient" is "5".If the value is large for example "506" of dividend and "8" of divisor means, first we sho...

How To: Find a missing angle in a parallelogram

Could you use a little help figuring out how to find an unknown angle in a paralellogram? Watch this free video geometry lesson. From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just finish your homework or study for that next big test). With this free math tutorial, you'll learn how to calculate a missing angle in ...

How To: Simplify complex fractions with variables

In order to simplify complex variables, you must first consider the numerical values separate from the variable. In the case of 24x/48x, you would look at the numbers alone to see if they have any factors. These numbers have the number 6 in common. So, divide it by 6. This will give you 4/8. This still requires some simplification. Two is still a factor for both. So, divide it again by four. This will give you 1/2. Now, if the numerator was raised to the second power, in the original equation...

How To: Use the Empirical Rule w/ standard normal distribution

In this video tutorial the instructor explains about the concepts of standard normal distribution and the empirical rule and how to use it to solve an exercise. He starts by explaining about standard normal deviation saying that in a standard normal deviation the value of mean is zero and the value of standard deviation is one. Now he draws the standard normal deviation by drawing a bell curve on an axis. Now he points the mean and standard deviations on it. Now using these concepts he goes o...

How To: Find the equation of a line given 1 point

Need help figuring out how to find the equation of a line given a single point? Learn how with this free video lesson. From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps (or just finish your homework or study for that next big test).

How To: Solve a number sequence

Check out this instructional math video that demonstrates how to solve a number sequence. These are basically a list of numbers, and there's a pattern to figuring out which number will come next. In the 15th lesson, learn how to solve SAT problems using the Official SAT Study Guide. Here are the math problems and their page numbers that this video covers:

How To: Draw a rhombus from Geometry

In this video the author shows how to draw a rhombus when given with the values of long diagonal (D) and a short diagonal (d). Now he draws the long diagonal of size D horizontally on a sheet of paper. Now he points the mid point of the line as he explains that the diagonals of a rhombus meet at midpoints. So now he takes the ruler and draws an another line perpendicular to the first line through its marked mid point such that the length of the perpendicular line is d/2 both above and below t...

How To: Calculate the width of a fence given its length and perimeter

From Ramanujan to calculus co-creator Gottfried Leibniz, many of the world's best and brightest mathematical minds have belonged to autodidacts. And, thanks to the Internet, it's easier than ever to follow in their footsteps. With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to find the width of a fence when given numbers for its length and perimeter.

How To: Use a protractor to make a pie chart

If you have a circular or semicircular protractor like the one used in this video, making a pie chart is as easy as – well — pie. This will teach you how to use your protractor to measure out each individual slice in your pie chart. Learn how to visualize statistical data through hand-drawn pie charts with this free video math lesson.

How To: Solve direct proportions

You can solve any proportion using the fundamental rule of proportions. First you must build the proportion if you are given a word problem. Decide using logic whether it is a direct proportion (more on one side means more on the other). If so, find the parts of the equation that use the same units and make a fraction with these, putting the smaller number on top. The number left over is linked with one of the other two numbers in the fraction--use logic to figure out which. Put it in the sam...