Math How-Tos

How To: Add fractions with like and unlike denominators

This video shows a tutorial of adding fractions. The first example shows a fraction that has like denominators so all you had to do is add the denominators. In the second example it shows two fractions that do not have like denominators. Therefore, you need to find the greatest common factor among the two denominators. Once this is found, you multiply the fraction on both the numerator and denominator to make both of the fractions match. Then all that is left is to add the numerators to finis...

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: Calculate and solve for density

Density is a means of representing how much mass is contained in the body of an object. The basic formula is: Density (D) = Mass (M) / Volume (V) so D=M/V. Density is important to know for buoyancy and to understand how heavy an object is. This video will show you three examples of measuring density so you can learn and put it to good use.

How To: Multiply decimals together

This video is about multiplying decimals together. The numbers to be multiplied are 1.003 times 2.8. First, you multiply like you would normally. Apply the number of decimal places. Count total number of digits to the right of the decimals. In this case it four. Apply the number of decimal places to the result. Starting from the right move four decimal places. Put the decimal point after the "2".

How To: Find the areas of a parallelogram and a triangle

The video teaches the viewer how to find the area of a parallelogram and the area of a triangle. For a parallelogram, the first step is to find the right angle, the line perpendicular to the base (this is a line you draw, not part of the parallelogram). The height of the line that forms this right angle with the base is the perpendicular height. Next, find the length of the base. The area is the base times the height. For a triangle, find the right angle with the base (again a line you draw)....

How To: Add decimals

This video explains how to easy add decimals. Adding decimals can seem to be a tedious job, and a single mistake can result in a completely different number. In reality, it is quite easy, and with a good method and some practice it can be done quickly. Write the two sets of numbers out, lining them up in columns. Keep the decimal points on top of each other and line up the non-decimals with non-decimals and the decimals with decimals. Start at the right-most column and add it up. If it become...

How To: Divide variables

This is a helpful video provided by Math Problem Generator. It deals with the complex challenges of dividing variables. The audio is great and provides specific examples of dealing with multiple types of this problem. The video lays out three simple steps. The first being to simplify the coefficient, the second being to divide the variable, and the third being to deal with the results of the division. The information is clearly presented and best of all it's free. I think we all wish there we...

How To: Find the area of a triangle in geometry

This is a tutorial on how to find the area of a triangle. To show the viewer how it is done, the video walks us through a simple example step by step. The first step is to find the base and the height (in this example 5 and 6). The next step is to multiply them together (making 30). Next, the answer is divided by two (to get 15). Finally, the units are written next to the answer (in this case inches squared). This is beneficial as it is a very easy and user friendly way of learning how to fin...

How To: Reduce fractions for easier manipulation

You should always try to reduce a fraction until it can't be reduced anymore. To do this, look at your fraction and figure out the greatest number BOTH the numerator and denominator can be divided by. This is called the GCF - the greatest common factor. In the video, the problem you must solve is (15/18). What number can be divided into both 15 and 18 evenly? The answer is 3.

How To: Find r-value & equation of regression line w/ EL531W

Need a little help in your Statistics class? In this statistics tutorial hosted by The Free Math Tutor, a demonstration of how to use the Sharp EL531W calculator to find the correlation coefficient (r-value) and the equation of a regression line is given. Want some more practice? For exercises and answer sheets, go here.

How To: Multiply fractions

Doug Simms gives a demonstration of multiplying fraction in a simple and easy manner. The simplest problems have proper fractions to be multiplied by proper fractions, and the answer can be arrived at by simply multiplying the numerator (upper value) of one fraction with the numerator of the other, carrying out the same operation with the denominators (lower values) of the two fractions, and finally, reducing the resultant fraction by a common factor, if any. Doug also gives three other examp...

How To: Use the SOH formula in trigonometry

Need a little help in your Trig class? In this two-part math tutorial, learn how to use the SOH (sine = opposite over hypotenuse) formula in high school Trigonometry. If you'd like to practice with exercises and answer sheets, you can go here.

How To: Divide fractions

Need a little help in the fraction department? Don't sweat it. Luckily, there is this two-part math tutorial on the subject of dividing fractions to help you along the way. In part one, learn how to divide proper fractions an in part two, learn how to divide mixed numbers with whole numbers.

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: Learn Calculus in 20 minutes

Did you sleep all semester in your Calculus class? Are you just waking up now to realize you have a test on Monday and that you're totally screwed? Well, luckily you can learn an entire semester worth of Calculus in just twenty minutes... or at leasts that's the hope.

How To: Calculate standard deviation

Looking to find the standard deviation of your set of values? Standard deviation quantifies how diverse the values of your data set are, and is useful in determining how different your numbers are from each other.

How To: Calculate percentage

Not sure exactly how to calculate a twenty percent tip for your waitress? Or how about how to figure out how much less your cost will be with that thirty percent off tag? Use these steps to calculate percentage, without a calculator.

How To: Find the slope of a line

Learn how to find the slope of a line in this math tutorial. Whether you're doing your math homework or trying to figure out how steep a mountain is, the slope of a line is simple to calculate and has many practical uses.

How To: Add fractions with unlike denominators using the lcd

Fractions can be tough, but in truth, they're one of the easiest concepts to understand in math. Figuring out fractions is the last thing you really have to worry about in math class, unless you have a horrible teacher, then you might want to check out this video tutorial to help you learn how to add fractions with unlike denominators, including how to find the LCD (lowest common denominator).

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: Add and simplify fractions

Ah, adding fractions. It brings back memories of awkward elementary school yearbook photos with braces and having a crush on our super hot Brad Pitt lookalike math teacher. But we digress.

How To: Calculate GPA

If you fear you're off to summer school, ease the stress of uncertainty with some simple math and know when to seek help with your grades.

How To: Solve quadratic inequalities in calculus

Calculus can be a bit tricky, but don't worry, Watch Math is here to help you out. Watch this math video lesson to learn how to solve quadratic inequalities in calculus. There's no better way to learn mathematics than from an advanced mathematician, like this PhD.

How To: Multiply and divide fractions in algebra

This video demonstrates how to multiply and divide fractions in algebra. From the people who brought you the Dummies instructional book series, brings you the same non-intimidating guides in video form. Watch this video tutorial to learn how to multiply and divide fractions in algebra, For Dummies.

How To: Integrate by parts in calculus

From the people who brought you the Dummies instructional book series, brings you the same non-intimidating guides in video form. This is Mathematics for Dummies. Just watch this video tutorial to learn how to integrate by parts, For Dummies.