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How To: Find the surface area of an aluminum can or cylinder

This video tells us the method to find the surface area of an aluminium can or cylinder. The surface area includes the outside area of the curved portion and the aluminium top and bottom. The formula to find area is the multiple of 2, pi, r, r+h or (2)(pi)(r)(r+h). The radius of the cylinder is the radius of the circular top or bottom. In the example shown in the video, the radius is 4 inches and the height is 12 inches. Substituting the values in the formula, we get the surface area as (2)(3...

How To: Draw a rectangle

In this tutorial the author shows how to draw a rectangle with given base b and height h values. First she uses a ruler to draw a horizontal base line of b cm. Now she uses a protractor and marks a 90 degree angle at one end of the line, then draws a straight line of h cm which is the height of the rectangle. Now she finishes the remaining part of the rectangle by drawing similar lines of the other sides. This video clearly explains how to draw a rectangle given the values of its base and hei...

How To: Find the area of a circle with a given radius

This video describes how to find the area of a circle given a radius of 4cm. The video begins by describing the formulas needed to find the area of the circle. The narrator cautions the viewer on a few common mistakes that people frequently make while using these formulas, such as not properly squaring the radius of the circle. The solution to the formula for a 4cm radius is 50.24 cm^2. The video then demonstrates that this value makes sense by overlaying a grid onto the circle and visually s...

How To: Simplify expressions involving absolute value

Need to know how to simplify expressions involving absolute values? It's an absolute cinch. 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). With this free math tutorial, you'll learn how to divide one fraction into an...

How To: Draw a circle with a compass for Geometry

The first thing you have to do is draw a line of the same length as the radius of the circle you want to draw. Then, open the compass the same size as the line length you draw is. Rotate the compass and you will create a circle. Please note that drawing this on a single sheet of paper can be difficult because the paper can move. Also, you can try rotating the paper, instead of the compass.

How To: Find determinants with a TI-83 calculator

Looking for a primer on how to find determinants using a TI-83 graphing calculator? See how it's done with this free video math 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: Graph inequalities on a number line

In this video, we learn how to graph inequalities on a number line. Inequalities have a greater than or less than sign instead of an equal signs. Remember that these are no different than figuring out how to graph normal equations. First, you will need to remove the single numbers from each side of the equation. Continue to do math on the equation until you figure out what 'x' is. From here, draw the numbers on your graph and then find the number that 'x' is greater to or less than. Use an op...

How To: Complete Fahrenheit to Celsius conversion

This video shows you how to convert temperatures from Fahrenheit(F) to Celsius(C). In the video, the example of 75 degrees F is used. The formula for converting Fahrenheit to Celsius is given by temperature in Celsius= (temperature in Fahrenheit- 32)/1.8. So for 75 degrees F we take 75 in place of temperature in Fahrenheit. Therefore the equation becomes (75-32)/1.8=C . Further 43/1.8=c and finally C= 24. Hence 75 degrees Fahrenheit= 24 degrees Celsius . This conversion is used as Celsius is ...

How To: Find the volume of a cylinder quickly

In this video the tutor shows how to find the volume of a cylinder. He relates the cylinder to real world examples of cans etc. Now he states the formula of the volume of the cylinder as the area of the base circle multiplied by the height of the cylinder. So the formula turns out to be V = Pi * r * r * h, where r is the radius of the base circle and h is the height of the cylinder. He solves a sample example to give you the idea of the problem. This video shows you how to find out the volume...

How To: Use rise over run to graph a straight line

In this video the tutor shows how to graph a straight line using the rise over run method. The rise over run trick allows you to graph a straight line as long as you have a starting point and a slope value in the form of a fraction. The first step is to graph the starting point. In the second step he states that the numerator of the slope is rise and the denominator of the slope is run. He says that the rise is vertical and the run is horizontal and shows how do rise and run using those value...

How To: Simplify radicals before adding or subtracting

This video in the Education category will show you how to simplify radicals before adding or subtracting. By doing this you will find all like radicals which will then ensure that you have all radicals in the simplest form. Let’s say you want to subtract square root of 45 from 3 square roots of 20. Now square root of 45 can be written as square root of 9 x square root of 5. Because, 9 and 5 are factors of 45. Similarly, 3 square roots of 20 can be simplified to 3 x square root of 4 x square r...

How To: Use radical notation to evaluate rational exponents

Learn how to evaluate rational exponents using radical notation in this free video algebra 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 study for that next big test).

How To: Solve equations with algebraic variables on both sides

In basic algebraic equations all the variables are on left side of the equation. But as the complexity of the problems increases you will find that the equations will contain variables on both sides of the equation. To solve these kinds of problems first simplify the equations on each side of the equation. You can use the distributive law to do this. Next try to cancel the variable on the right side of equation by adding the negative value of that variable to both the sides of the equation. N...

How To: Convert temperature using a point slope equation

In this video the instructor shows how to convert temperature using the point slope form. In this kind of problem sometimes you are given a temperature in Fahrenheit and its equivalent in Celsius and an other temperature similarly in both Fahrenheit and Celsius. Now you are asked to find a linear equation for these pair of temperatures. To solve these kind of problems assume that the given temperatures represent the point (x, y). Now you have two points. Substitute this value in the point slo...

How To: Convert a decimal number into a fraction

Need to know how to convert a decimal number into a fraction in basic arithmetic? It's simple. 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). Convert a decimal number into a fraction.

How To: Graph an inequality in slope-intercept form

This how to video shows you how to graph an inequality in slope intercept form. First, graph the line. Depending on the inequality, use a dash or solid line. Use a solid line for less than or equal to or greater than or equal to. Use a dash line for greater than or less than. If y is less than or less than or equal to, shade the bottom area of the line. If it is y is greater than or greater than or equal to, shade the top area of the line. Check your answer by substituting in any point from t...

How To: Find percent

Finding the percent of a given value is made simple and easy in this math tutorial video. In step one you must divide the part or the portion by the whole. As a result we obtain a decimal number. In step two, we must then move the decimal point two places to the right in order to convert the number into a percent value. This brief video tutorial illustrates the process in these two steps and makes it simple for anyone to be able to obtain a percent value for a portion of a whole.

How To: Use interval notation to express inequalities

Could you use a little help figuring out how to use interval notation to express inequalties? 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 give inequalities in interval nota...

How To: Convert large numbers into scientific notation

Confused about scientific notation? In this informative video, Doug Simms from free math tutoring helps you work with large numbers more efficiently by converting them into scientific notation. Let this expert walk you through easy to understand marker board examples covering all of the basics of scientific notation, including exponents, decimals, and how to convert numbers back and forth between different notation forms. Don't let confusing science problems get you down when Doug Simms is ar...

How To: Convert decimeters to kilometers 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 convert between decimeters and kilometers in basic mathematics.

How To: Find the surface area of a rectangular prism

Have a 3 dimensional figure that you can not figure out the surface area? This video teaches the fundamental concepts and techniques of figuring out the surface area of a 3 dimension figure. In this video, the specific shape will be a rectangular prism. The video will assist its viewers in understanding and learning the process of how to find the surface area of this 3 dimensional figure. The method is simple and easy to learn. This is highly recommended to anyone with an interest in math.

How To: Figure out the slope of a line

In this video you will learn how to find a slope of a line. The man in the video shows in a practical and easy way, how to do it with formulas. First he teaches how to find slopes of lines containing both negative and positive points. He shows with formulas how to do it. He teaches how to find slopes on a flat line and demonstrates that the slope of it is equal to 0. Next, he teaches a "trick" to help students learn how to identify zero and no slope lines. In the last example, he demonstrates...

How To: Find the mean of a set of numbers

Need to find the mean (that is, the regular average) of a set of numbers? It's easy! So easy, in fact, that this clip can present an overview in just under 45 seconds' time. 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 te...

How To: Factor quadratic trinomials by trial and error

Want to know how to factor quadratic trinomials in algebra? One easy way is through trial and error. Watch this free video algebra lesson to see how. 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 factor t...

How To: Find oblique asymptotes of rational functions

This is a great instructional video on how to find oblique asymptotes of rational functions. Let us take the example f(x)= x square+4x-12 over x-6. Now we have to find the horizontal or oblique asymptotes of this rational function. The higher power here is x square which is at the top and hence we have to find oblique asymptotes of this function.When we divide x square+4x-12 by x-6 we get x=10 and the reminder is 48. Now you can easily write down the final answer. The oblique asymptote for th...

How To: Understand & calculate percentages with word problems

This video begins with teaching of percentage lesson. He is also teaching conversion of percentage to decimal and vise verse. This teaching is using advanced technology note pad when he goes on writing on pad that will display on screen. He is telling that percent 35% in decimal it is .35 and if decimal 2 it is 20% in percent. And he was teaching how to convert fraction to percent by taking one example 7/8 , to convert this first we have to divide 7 by 8 then we get answer .875 then to conver...

How To: Solve an equation by the distributive property

In this simple tutorial the tutor shows how to solve equation by the distributive property. He states that when there is a number which is multiplied to a full equation, we have to multiply each and every term of that equation by that multiplying number. This is called the distributive property as the value is distributed to each and every term inside the equation. He goes on and solves a problem based on this property to give a clear idea of the property. This video shows how to solve equati...

How To: Use optimization methods in calculus

This video shows how to use optimization methods in calculus. Optimization means finding the maximum or minimum values of a quantity or finding when the maximum or minimum occurs.What quantities are optimized in economics?we want to minimize costs or maximize revenue.First steps in any optimization problem1.Identify the quantity to be optimized i.e., read the problem exactly what is exactly maximized or minimized.2.Identified the feasible domain. This is important because the math we can opti...

How To: Multiply simple fractions

Watch this video to learn how to multiply fractions by fractions. First multiply the top numbers together. For example, if you have 3/5 * 4/7, multiply 3 * 4 and put your product on top of the fraction you will get as a product. Next, multiply the bottom numbers together and put them on the bottom of your resulting fraction. Next see if you can reduce your product to simplify it. You could also do the reducing step first by canceling out any common factors in the numerators and denominators o...

How To: Convert recurring decimals to fractions

In this video we learn how to convert recurring decimals to fractions. Start off by writing out the decimal with the dot next to it to show that it's recurring. This means that the number goes on forever and doesn't stop. To convert this to a fraction, write down the number as the numerator. On the bottom you will put the number 9 always. Now, you can divide these two numbers with each other using a calculator. Once you do this, you will get the correct answer. Once you divide it out, you wil...

How To: Multiple and divide rational expressions

This video walks you through the steps of multiply and divide rational expressions. This excellent video shows you a clean board, with the instructors voice showing exactly what to do. Don't fret, any question you may have, will be answered. Watching this video will make you feel like your back in the classroom but rather comfortably from your home.

How To: Find the area of a trapezoid

In this video, we learn how to find the area of a trapezoid. The formula to figure out how to find the answer is: Area= 1/2x (base1 x base2) x height. Now, find the bases and the height of the trapezoid. Remember that the height must always be perpendicular to the bases. Once you have found these, add the bases and multiply by the height. You can use a calculator to do this or do it off hand if you're good with math. For the third step, divide the answer by 2 and then write down the answers w...

How To: Apply the 2nd Law of Exponents

Having trouble dividing exponents? Doug Simms from Free Math Tutoring provides an excellent tutorial on applying the 2nd Law of Exponents. If you need to know how to divide polynomials, watch this video covering easy to follow examples explaining and demonstrating the 2nd Law of Exponents. In this first part of a two video series, Doug's student explains how to subtract the exponents within a polynomial in a simple example that will help you leap over this common math homework hurdle.

How To: Divide mixed numbers quickly and easily

Dividing mixed numbers may seem like a complicated operation. However, this brief video makes it simple. The illustrations in this video show you step-by-step how to divide mixed numbers using a very simple method. It involves taking the reciprocal of the second fraction. This math tutorial takes you the rest of the way and simplifies mixed number problems.

How To: Find the area of a circle with pi

This video shows how to find the area of a circle using a formula. The formula for area of circle is pie multiplied by square of radius. Pie is actually an infinite number but for the sake of convenience we consider the value of pie as 3.14. So we multiply the square of radius with 3.14. Radius is the distance between the center point of the circle to any of the outside arcs. It is actually half of the diameter (diameter is the distance between two arcs of a circle). As an example here the ra...

How To: Add and subtract rational expressions in algebra

In this math tutorial, you'll be trained in the arcane art of adding and subtracting rational expressions by finding the common denominator. A skill many discard upon leaving middle school, it is used by the villians who operate under the acronym "SAT" to test those caught blank minded and whose minds are unrationalized.