### How To: Find the perimeter & area of a complex figure

In this video tutorial the author shows how to find the perimeter and area of a complex figure. He shows that a complex figure can be subdivided into standard geometric figures. In the current example he divides the complex figure into a rectangle and a triangle. Now he computes the perimeter by adding the three sides of the rectangle and the two sides of the triangle. Similarly he computes the individual areas of the rectangle and the triangle and finally adds then up to find the area of the...

### How To: Determine if you have a function

In this tutorial, we learn how to determine if you have a function. You will start off with two functions and their points. The 'x' values make up the domain of the function and the 'y' values make up the range. The input values are the domain and the output are the range. If you're checking to see if you have a function, you will need one 'y' for every 'x'. This means that each value has another one that goes with it. Each of the points need to have one partner with them, no more and no less...

### How To: Find a number given Its percent

This how-to video is about how to find a number when its percent is given. This video is really helpful and effective in finding the number when the percent is given, the following steps are explained in the video to find the number when its percent is given:

### How To: Factor the sum and difference of cubes

Need to know how to factor the sum or difference of two cubes? Learn how with 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: Calculate percent yield

This video shows you how to calculate the percentage yield in chemistry. To find the percentage yield, you will need to divide the actual yield by the theoretical yield. Then, multiply it by 100: i.e. % yield = actual yield/theoretical yield x 100. An actual yield is the amount of a substance produced in an actual laboratory experiment. It is based on an actual physical measurement of a quantity. The theoretical yield is the yield as is calculated on paper: i.e. through calculations. Therefor...

### How To: Find standard deviation

In this video tutorial, viewers learn how to calculate the standard deviation of a data set. The standard deviation of a statistical population, a data set, or a probability distribution is the square root of its variance. To calculate the standard deviation, users will need to follow these steps. 1) Find the mean of the data. 2) Subtract the mean from each data point. 3) Square each of the values you got in step 2. 4) Then find the mean of the values you get from step 3. 5) Finally, square r...

### How To: Find the slope of a line given 2 points with fractions

In this video tutorial the instructor shows how to find the slope of a line given two points with fractional values. To do this first name your two points as point 1 with coordinates as x1, y1 and point 2 with coordinates x2, y2. Then substitute the values in the equation of the slope which is slope m = (y2 - y1) / (x2 - x1). Now all you have to do is simply the fraction after substituting the point values. Be careful about the signs while substituting in the formula. Now finally after solvin...

### How To: Find the slope, given a graph

If you watch this video, you will learn what slope is, and how to find it. Slope is defined as rise divided by run, where rise in the increase the Y coordinate and run is the increase in the X coordinate. For example, if you pick two points, you can travel from the left point to the right point. However many points you go is the run. How far up you go is the rise. For example, if your rise is 4 and your run is 2, then you divide 4 by 2 to get your slope, 2. When you're finding the rise, if yo...

### How To: Use ">" (greater than) and "<" (less than) symbols

In this video the author explains how to identify the less than (<) and greater than (>) symbols and when to use them. She explains to us to relate the numbers to animals stating that the smaller numbers are smaller animals and bigger numbers are bigger animals. Now she tells us to imagine that smaller animals are eaten up by the larger animals. So she shows a smaller number comes on the left side of '<' sign and bigger number comes on the right side of '<' sign stating that the bigger number...

### How To: Subtract a mixed number from a proper fraction 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 free math tutorial, you'll learn how to subtract a mixed number from a fraction in basic arithmetic.

### How To: Find a slope of a straight line with: Ax + By + C = 0

In this video the instructor shows how to find the slope of an equation which is in the form Ax + By + C = 0. He says that the formula to find the slope of a line in the above form is slope m = -A/B, where A and B are the numeric constants of the variables x and y in the given equation. He goes on and further shows how to do this with a couple of examples. He shows how to reduce any equation into the general form and how to apply the slope formula then. This video shows how to find the slope ...

### How To: Find the standard deviation with the Z-Score formula

In this tutorial, we learn how to find the standard deviation with the Z-Score formula. First, take your problem and write it out one by one underneath each other. Then, you will need to substitute the numbers in for the variables that are in the problem. Once you do this, you will follow the basic rules of math to find out what the answer to the problem is appropriately. Once you have done this, finish off the problem to find the answer, then you will have found the standard deviation using ...

### How To: Figure out the domain & range of a piecewise function

Need to calculate the domain and range of a graphed piecewise function? 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: Prove a triangle inscribed in a circle is right angled

When a triangle is inserted in a circle in such a way that one of the side of the triangle is diameter of the circle then the triangle is right triangle. To prove this first draw the figure of a circle. Now draw a diameter to it. It can be any line passing through the center of the circle and touching the sides of it. Now making this as the side of a triangle draw two lines from the ends of the diameter to a point on the circle. Now join the center of the circle to the other vertex of the cir...

### How To: Find the circumference of a circle

Use a simple mathematical formula to find the circumference of a circle. The circumference of a circle can be determined by using the formula 2 times pi times the circle's radius. Pi is equal to 3.14. If a circle's radius is 10 centimeters, first multiply pi times 2. Pi, or 3.14, times 2 is 6.28. The next step then is to multiply 6.28 times the circle's radius. Since the circle's radius is 10 centimeters, multiply it by 6.28. This gives you 60.28. 60.28 inches, then, is the circumference of t...

### How To: Find the Slope Given 2 Ordered Pairs

Slope is the change in Y over the change in X. Written out, the formula looks is as follows: (y2-y1)

### How To: Solve an equation with a radical under a radical

In this video the instructor shows how to solve an equation with a radical under a radical. If you have an equation with a square root on both sides, with one of the sides having another inner square root under the original square root, it can be a little tricky to solve it.

### How To: Change Fahrenheit to Celsius

This video is a tutorial on how to convert Celsius to Fahrenheit. The title of the film says it will teach you how to convert Fahrenheit to Celsius, but it does not. It does just the opposite. The video begins by comparing Fahrenheit and Celsius. He points out that Fahrenheit measures water to freeze at 32 and water to boil at 212. Celsius measures water to freeze at 0 and water to boil at 100. To convert Celsius to Fahrenheit, multiply the Celsius temperature by 1.8 and add 32. Many countrie...

### How To: Simplify a quadratic formula result

In this video the tutor shows how to simplify a quadratic formula result. You can solve a quadratic equation using the quadratic formula. The first thing you have to do when given the quadratic equation is bring all the terms to one side so that you have a zero on the other side of the equals to sign. Now the formula to calculate the roots of the quadratic equation ax*x + bx + c = 0 is x = (-b + root of(b*b - 4*a*c) ) / 2 * a. The other root can be obtained by using the minus sign before the ...

### How To: Clear fractions from linear equations in Algebra

Need help figuring out how to remove fractions from linear equations in algebra? 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: 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: Use a TI-89 to calculate nCr

This video shows you how to do a mathematical representation on computing the nCr function using a TI-89 calculator. You can write the nCr notation in different forms. It can be simplified from nCr to C(n,r). The symbol can either be read "n choose r" or "n taken r at a time" which are from it's probability applications. On the example to find "26 choose 17", go to the Home screen of the TI-89 calculator and then go 2nd 5 which is Math. Go choose probability and then to nCr to type in (26,17)...

### How To: Find the equation of a circle given: center & tangent

In this video, the instructor shows how to find the equation of a circle given its center point and a tangent line to it. To do this, take a graph and plot the given point and the tangent on that graph. Now, from the center of the circle, measure the perpendicular distance to the tangent line. This gives us the radius of the circle. Using the center point and the radius, you can find the equation of the circle using the general circle formula (x-h)*(x-h) + (y-k)*(y-k) = r*r, where (h,k) is th...

### How To: Apply the 4th Law of Exponents

This how-to video is about Fourth Law of Exponents. Before going to see this let's first know what the fourth law of exponent says. The fourth law of exponents says that "any value other than zero brought to an exponent of zero is equal to one".

### How To: Solve rate 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 rate problems in algebra using the distance formula.

### How To: Express inequalities using interval notation

With all the subjects offered in junior high and high school, math isn't a favorite for many. It can often times be confusing and although the results are concrete and don't require anybody to be imaginative, it can still pose a problem. In this tutorial, you'll find out how to express inequalities using interval notation. Good luck and enjoy!

### How To: Find outliers using the Z-score method

If you use Microsoft Excel on a regular basis, odds are you work with numbers. Put those numbers to work. Statistical analysis allows you to find patterns, trends and probabilities within your data. In this MS Excel tutorial from everyone's favorite Excel guru, YouTube's ExcelsFun, the 49th installment in his "Excel Statistics" series of free video lessons, you'll learn how to find outliers with the +/- 3 Z-score rule and the ABS function. See how to do a box plot by hand and in Excel. For th...

### How To: Convert temperature using y = mx + b

In this video the instructor shows how to do temperature conversions using y = m*x + b. Now if Celsius is represented by the variable C and Fahrenheit is represented by the symbol F, you can replace then in the previous equation in place of the variables x and y giving you the equation C = m*F + b. Now to solve for the values of the constants m and b you need to have values of two sample temperatures in both Celsius and Fahrenheit. Take the first sample and substitute in the above equation gi...

### How To: Simplify algebraic equations w/ the minus-one trick

Just follow a few steps to simplify algebra with the minus one trick. First step is to take two algebraic equations with having numerator and denominator algebraic equations. Second step is to divide the denominator with numerator. For example, it have like -c/c, it gives like answer as -1, but we have another type like (c-a)/(a-c) - to solve these types of steps, like multiply numerator with minus(-), it gives the common the minus and -(a-c)/(a-c), then it gives -1 as a answer.

### How To: Find the vertical asymptotes of rational functions

To find a vertical asymptote, you are trying to find values of x that produce 0 in the denominator but not in the numerator. If 0/0 occurs, that means you have a "hole" in the graph. A vertical asymptote is a place in the graph of infinite discontinuity, where the graph spikes off to positive or negative infinity. To find the vertical asymptote, set the denominator equal to zero and solve for x. Check that the values also do not give a zero in the nominator. If the values work, you have found...

### 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: Understand the differences / similarities between squares, rectangles & rhombi

This math lesson from Yay Math covers four-sided shapes in geometry. Learn about the differences and similarities between rectangles, squares and rhombi (the plural of rhombus). The properties of rhombi and squares are covered, so sit back and enjoy this educational (and FUN) math lesson.

### How To: Divide and give an answer as a fraction

In this video we learn how to divide and give an answer as a fraction. If you are starting out with a simple fraction, you will simply take the number before the divide sign on the top and the second number on the bottom. If you end up with a number that is able to be simplified, make sure you take it down to it's most simple version possible. You can end up with a top heavy fraction, which means there will be whole numbers involved. Do the division to figure out how many times the bottom num...

### How To: Bisect a line segment

In this tutorial, we learn how to bisect a line segment. First, you need to adjust your compass so the distance from the sharp part and the drawing part is the size of the line. Then, put the sharp part on one side and draw your arc with the pencil. Do this on both sides of the line so your image shows two arcs that intersect each other. Since you have these two intersecting lines, you can draw a line between these to show where the middle of the line would be. Use a ruler to draw this straig...

### How To: Graph a linear equation using slope-intercept form

Are you "just not a math person"? Hogwash. Everyone seems to think that at one point in their life. With a little practice and study, math will become more and more easy to understand. Start your journey towards become a "math person" with help from this video, which teaches how to graph a linear equation using slope-intercept form.

### How To: Simplify square roots

This is a video tutorial on how to simplify square roots. To simplify square roots, one must have the knowledge of splitting numbers into prime factors. For example,12 can be split into 4*3 and further more into 2*2*3. Here we see that all the factors are prime numbers. So the square root of 12 can be written as 2*square root of 3(as shown in the video). The method used in the video is applicable for simplifying any square roots as any number can be split into prime factors. Follow the video ...

### How To: Use the substitution method to solve problems

This video teaches you how to use substitution to find the point on a graph (the x and y coordinates) where two separate equations would cross. Substitution is a trick of algebra that allows you to find this point without making a graph. The first step is to isolate one of the variables (x or y) in one of the equations. That way, you know that that variable is equal to everything on the other side of the equals sign from it. You can then take that whole side, and substitute it into the other ...

### How To: Solve rational inequalities (intermediate level)

Struggling with math homework? An expert instructor from Khan Academy helps you work your way through the challenges of solving more difficult rational inequalities. Provides fantastic animated examples that demonstrate helpful tips, overcoming common problems with inequalities, and "simplifying" the problems of inequality simplification! Covers tricky complications such as swapping inequalities, understanding constraints, working with negative numbers, and working with zeros in equations. Po...

### How To: Find the surface area of a cone without slant height

Math always seems hardest until someone shows you how to do the problem and then it all seems just so simple. This video will walk you through the process of finding the surface area of a cone when you also have to derive the slant height. Use this example to help with your other cone problems.

### How To: Calculate Faster Than a Calculator

When you need to crunch numbers quickly — and I mean really quickly — there's a cool method you can use to multiply two numbers together in just a few seconds.