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How To: Increase a number by a percentage in basic arithmetic

Need to know how to grow a quantity by a percentage? Learn 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 installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to increase a number by ...

How To: Solve percentage problems

Check out this instructional math lesson that demonstrates how to solve percentage problems. In the 13th 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 percentages using a standard calculator

Want to find a percentage of one number relative to another? With a calculator, it's easy. And this free video math lesson will show you how to go about it. 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 domain of a function in precalculus

Looking for a primer on how to find the domain of a function in precalculus? Learn how with this free video precalc 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: Calculate the probability of two dependent events

This video explains how to solve the problem of probability dependent events. In this video the problem is that a box contains three pens, 2 markers, and 1 highlighter. The person selects one item at random and does not return it to the box. So what is the probability that the person selects 1 pen and 1 marker. That is 6 items total. First she count the all items that involved in this problem. Then count the individual probability of the pen and marker. The person selects 3 pens out of 6 item...

How To: Simplify complex fraction w/ 3 fractions top & bottom

You Tube User robichaudd teaches you how to simplify a complex fraction with 3 fractions top and bottom. Your result should be 1 fraction over 1 fraction. To do this you must find the L.C.D. at the top, which x cubed. That is the largest variable there. Thus, the L.C.D. at the bottom is x squared. Now you want to make each x below the fraction line be x cubed, respectively x squared. You then have one large fraction over one large fraction. But that is just one large fraction multiplied by th...

How To: Factor trinomials with the "bottoms up" method

After an easy way to factor trinomials in algebra? Try the bottoms up method! 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 lowest common multiple with the ladder method

Looking for an easy way to find the lowest common multiple (LCM) of a pair of numbers in simple arithmetic? 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: Graph square root functions & inequalities

On Yay Math, Robert Ahdoot, founder of Yay Math, will show you some square root functions and some inequalities. He begins with the problem y=x². Then he makes a sketch with two intersecting lines in a t shape. The problem is illustrated by a curved U shape, the U's bottom resting on the horizontal bar, which represents x, while the center takes the vertical line. The vertical bar represents y. This U is directed up because the x² is a positive number. If the number were negative, the U would...

How To: Find coordinates (ordered pair)

This video tells you how to identify the coordinates of an ordered pair from a given point. An ordered pair is denoted by (x, y). Normally a graph has two axis, the x and the y axis. Consider a point on the graph. It will surely be the intersection of two values and one value will be from the x axis and the other valve from the y axis. Find the two corresponding values of the given intersection point. The value on the x axis will be x and the value from the y axis will be y. Now you have got ...

How To: Compute a square root using the geometric method

With mathematics, as with anything else, not everyone progresses at the same rate. Happily, in the age of Internet video tutorials, this isn't a problem. Those who progress quickly can go beyond what's being taught them and those who are struggling likewise have all the time in the world to catch up. With this free video math lesson, you'll learn how to calculate the value of a square using using geometry.

How To: Draw an isosceles trapezoid

This is a video tutorial in the Education category where you are going to learn how to draw an isosceles trapezoid. This video demonstrates how to draw an isosceles trapezoid with a long base (B), a short base (b) and a 35 degree angle. First you draw the long base. Now center the short base at the center point of the long base and mark the end points of the short base with dots. Next draw perpendicular dotted lines from the dots extending upwards. Draw 35 degree angles from either end of the...

How To: Solve a system of linear equations with a TI-89

Looking for instructions on how to solve systems of linear equations using a TI-89 graphing calculator? 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 finish your homework or study for that next big test).

How To: Do long division with remainders

This video goes through the step by step process of doing long division with remainders. Multiple examples are used throughout the video to give the viewer a better idea of how to properly complete the difficult task. Perfect for anyone learning long division for the first time, or for anyone attempting to relearn long division after forgetting how to do the process (an all to common occurrence in a world with calculators on every cell phone).

How To: Find the nth term of a geometric sequence

Looking for a primer on how to find the nth term of a geometric sequence? See how it's done with this free geometer's 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 (or just finish your homework or study for that next big test).

How To: Find the slant asymptote of a rational function

Need help figuring out how to calculate the slant asymptote of a rational 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: Find the equation of trig functions by their graphs

Need to know how to determine the equations of trigonmetric functions by inspecting their graphs? Learn how. Learn how to use trigonometric functions to calculate the sides of a right triangle. Need to know how to solve a matrix-form linear equation 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 f...

How To: Do long division quickly

In this `Math Made Easy' tutorial the instructor shows how to perform Long Division. He gives a simple four step approach where in the first step he shows to divide the first left most number by the divisor and this gives the quotient. Now he shows to multiply the quotient with the divisor to get a value which is to be subtracted from the original divided number. Now in the third step he shows how to bring down the next digit and finally in the last step he asks to perform the same procedure ...

How To: Divide fractions by multiplying by the reciprocal

Having a hard time with dividing fractions? Learn the simple steps it takes to complete these division problems. With this instructional educational video you learn the golden rule, "NEVER DIVIDE FRACTIONS" Instead you multiply by the reciprocal which is the flipped version of the original fraction. Then from there is simple, you just multiply straight across like any other multiplication problem then just simplify. This one minute video will take you through all the steps and give you an exa...

How To: Find the perimeter & area of a rectangle

This video starts out with a basic view of a rectangle and its dimensions. The base is 7 inches while the sides are 4 inches. It then displays the formula for finding the perimeter of the rectangle which is the addition of both bases and both sides. After the substitution of the values into the formula you can quickly come up with the perimeter. Then moving on the area, the formula is the base multiplied by the side. In this case, the base being 7 inches and the side being 4 inches you come o...

How To: Identify the numerical coefficient of a monomial

In this tutorial the instructor discusses about the numeric coefficients that we come across while we work with polynomials. He goes on to discuss the numerical coefficient of a monomial stating that it is the number that is present before the variable in the monomial. He states that the numerical coefficient can also be negative or if there is no number present in front of the variable, it indicates that the numerical coefficient is one. This video helps in understanding what the numerical c...

How To: Solving for "x" using multiplication and division

Solving for "x" using multiplication and divisionHere is a typical algebraic equation "2x=12". Multiplication in algebra will have the "x" next to a number. The process will be a combination of multiplication and division to solve for "x". To get "x" alone, we do the opposite operation. 2x/2=12/2. Bring down the "=". You must balance the equation to make sure you did the computation correctly. 2x6=12. Next, we have a multiplication and addition problem. 4x+7=15. We must get rid of the 7. +7-7...

How To: Use a TI89 calculator to graph linear equations

This video shows the user how to use a T189 calculator to plot linear equations. The video demonstration is done using an ‘on screen’ representation of the calculator – there are also verbal instructions. The equations are plotted on the same axis by selecting the ‘y=’ function. The corresponding values of y in terms of x are then inputted into the graphical calculator. Once this has been done for every equation you can get the calculator to display the graph. This then allows you to compare ...

How To: Stretch, shift & reflect the graph of a square root

Professor ElvisZap teaches you how to stretch shift and reflect the graph of a square root. A square root function is the opposite of a squared function. You start with y=square root of (x-1) it becomes 0<=x-1. then 1 <=x. You use the graph and solve it as you would for any function using small values first, then you have y=square root of x - 1, the domain 0<=x. This shifted the graph down 1 unit. 0=square root of x - 1, 1=square root of x, 1=x. Then the range is [-1 + infinity). Continue in ...

How To: Use the TOA formula in trigonometry

The video is a tutorial in trigonometry. The teacher teaches that the tangent or the tan of an angle is the ratio of the opposite side to the adjacent side of a right angled triangle. If one side and one angle is given then the value of the unknown side can be found by solving the equation tan of angle is equal to opposite upon adjacent side. If the angle is to be found then the tan inverse of the value is seen in the calculator.

How To: Find an LCM or GCF with the Indian method

Looking for an easy method for discovering the lowest common multiple (LCM) and/or greatest common factor for a set of numbers? Try the Indian method! 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 linear equations in the form of AX+B=C

Need to know how to solve AX+B=C-form linear equations 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 a system for solving line...

How To: Factor trinomials with 2 variables & GCF by grouping

In the video, the process of factoring trinomials is described. A trinomial that cannot be easily factored in its original form is shown. It is simplified by pulling out the greatest common factor. After that, a trinomial that is easier to factor is shown. Next, the simplified trinomial is broken up into four terms so that factoring by grouping can be done. Once again, a common factor from each pair is taken so that two binomials are created. Once the greatest common factor is added back with...

How To: Use the Quintile Formula in Statistics

In this tutorial, we learn how to use the Quintile Formula in Statistics. To find the quintile rank of a formula that is in a certain set, you will first need to count the number you are given. Then, read the equation so you understand what the R, N, equal side, and other numbers mean. Once you understand what all of these mean, fill in the formula with the correct information. Use the information you are given in the question to fill it into the equation. When finished, you will apply the ru...

How To: Complete the square to graph a quadratic function

In this tutorial the instructor shows how to complete the square to graph a quadratic function using transformations. You can do this by transforming your equation in a series of steps. First make the coefficient of the square term to one by pulling out its numerical coefficient. Now to complete the square of the first part add half the coefficient of the variable with a degree one. Now to maintain the original value of the equation also make sure that you subtract the same value from the equ...

How To: Interpret derivatives of marginal cost and revenue

This video tells us the method of interpreting derivatives of marginal cost and revenue. If C(x) is the cost of producing x units of a product, C(400) would be the cost to produce 400 units. Now marginal cost is the cost of producing one unit which is equal to the derivative of the cost function or C'(400) which is equal to limit of h tends to zero or lim h->0 [lim(400+h)-lim(400)]/h which is approximately equal to [lim(401)-lim(400)]/1. Similarly, if R(x) is your revenue function, marginal r...

How To: Draw a dotted/solid line when graphing an inequality

In this video the tutor shows when to use a dotted line and when to use a solid line while graphing lines in coordinate geometry. He says that we should use a dotted line to plot an inequality which contains the symbols less than or greater than. He also says that we should use a straight line when plotting an inequality which contains the signs less than or equal to and greater than or equal to. He goes on and demonstrates this idea with some examples. This video shows how to use different l...