Hot Math How-Tos
How To: Find the equations of parallel and perpendicular lines
A pair of straight lines can be parallel lines or perpendicular lines or neither. Two lines are said to be parallel when their slopes are equal. Two parallel lines never intersect each other. On the other hand two lines are perpendicular when the product of their slopes is equal to -1. Two perpendicular lines intersect only once and at right angles. So when you are given two lines and asked to find if they are parallel or perpendicular lines, first compute the slope of the lines. Identify two...
How To: Find the equation of a line in point-slope form
When you are given a point through which a line passes and the slope of that line, you can calculate the equation of that line. The general equation to solve this kind of equations is called as point-slope form. The point slope of a line passing through (a, b) with slope of m is (y - b) = m * (x - a). Now substituting the values in the above equation you can obtain the equation of the line in terms of x and y. In case you are given with two points first find the slope of the line which is the...
How To: Work with the coordinate plane in algebra
This video tells us the method to work with the coordinate plane in algebra. The first step tells us the method to determine the coordinates of a given point on the coordinate plane. For this, go parallel to the x axis from the given point and see where it intersects the y axis. This is the y coordinate. Again, go parallel to the y axis from the given point to the x axis. The point of its intersection with x axis is the x coordinate. Now we have the coordinates and we have to find the points ...
How To: Find an angle using alternate interior angles
In this video tutorial, viewers learn how to find an angle using alternate interior angles. Make sure that the angles are alternate interior angles. Alternate interior angles are angles that are on the inside of the parallel lines, and on the opposite side of the transverse. The transverse is the line that passe through the two parallel lines. If both angles are inside the line and are opposite to the transverse, then they are alternated interior angles. If you know two angles are alternate i...
How To: Properly read a decimal number
Decimal numbers are numbers which contain a integral part before a point and a decimal part after the point. The first step in solving decimal arithmetic is being able to understand decimal numbers. Reading a decimal number is similar to reading a whole number except for a few minor differences. In a normal number the right most digit is ones place and the place next to it is tens place and so on the value of the position increases as you move left. But a decimal number starts from a tenths p...
How To: Simplify rational radicals
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). With this free math lesson, you'll learn how to simplify rational radical expressions.
How To: Simplify radicals which are not perfect squares
Need help reducing radical expressions without perfect square or cube roots? Take heart: this free math lesson will ensure that you know everything you need to know for that next big test. Examples include square roots, cube roots, and 4th roots. You'll also learn a technique to simplify n-root expressions as well as how to simplify variables in radical expressions.
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: Change decimals to fractions
For certain equations, you will need to convert decimal numbers into fractions. If this is the case, there are a few quick steps you will need to take to do so.
How To: Convert percents into fractions
Percents are handy for displaying statistics or labeling objects such as sale items in a store, or ingredient labels. However, in a math equation, a percent is a bit difficult to use. Therefore, you will need to convert your percents into an easier type of number form.
How To: Change a fraction into a decimal
Sometimes it is much easier to work out an equation if your numbers are in decimal form instead of fractions. This is especially useful if you are using a basic calculator.
How To: Convert decimals into fractions and percents
Decimal numbers, fractions and percents are pretty much three versions of the exact same value. In this tutorial, learn how to work with all three and convert them within each other.
How To: Get a fraction from a recurring decimal
In order to pass that big Algebra test you will need to know how to get a fraction from a number with a recurring decimal. If you are looking for a shortcut, look no further than this tutorial.
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: Graph a line using points and slope
Given a point through which a line passes and the value of its slope you can graph the line. To do this first plot the given line. Now taking the slope and using the rise over run method plot a second point. Connect these two points and this gives you the graph of the line. Extend this line further on both sides to get the complete line. The point where this line cuts the x-axes is called the x-intercept and the point where this line cuts the y-axes is called the y-intercept. The important po...
How To: Add fractions with unlike denominators
Watch this video to learn how to add fractions with different denominators. Use the least common denominator method to add the different fractions together. After watching this 2 part video, you'll be more than satisfied with your ability to do this simple math trick! Put it into practice, and pretty soon you'll spit out answers in seconds!
How To: Solve a system of linear equations through graphing
This video shows the method to solve a pair of linear equations by plotting their graph. Look for points of intersection of the two graphs which is the solution. Let us solve 5x-y=6 and 2x+y=8. Writing the equations of lines in slope intercept form, we get y=5x-6 and y=-2x+8. Now we plot the two lines. For the slope 5 or 5/1, we go up 5 units and left 1 units from the point of intersection on the y axis. For -2 or -2/1, we go down 2 units and left 1 units from the point of intersection on the...
How To: Find surface area and volume of a sphere
In this how to video, you will learn how to find the volume of a sphere and surface area. Let's say you need to find the volume of a sphere with a surface area of 200 cm cubed. You will need to know the formulas for surface area and volume of a sphere. The formula for surface area is 4 pi r squared. The formula for volume is 4/3 pi r cubed. Plug in the surface area of 200 cm cubed and plug it into the formula. You should get an answer of about 3.99 cm. Now you just have to solve for the radiu...
How To: Find the median of a set of numbers
This is a how-to-video which demonstrates techniques to find the median of number in a series. This demonstration takes the following example.
How To: Add fractions with mixed numbers using math
When you start out using fractions, one of the first things you will learn is how to add and subtract them. In this tutorial, made specifically for beginners, you will learn the basics of adding fractions with mixed numbers. This is really not very hard and if you follow along with the step by step presented in this tutorial, you will have the hang of it in no time. Once you master this step, you will be well on your way to an A in your math class!
How To: Add or subtract fractions with different denominators
In this tutorial, you will learn about fractions. Fractions may look scary, but they are relatively easy to handle if you take your time. In this particular video, learn how to add or subtract fractions that have different denominators. You will learn how to reduce common fractions to the lowest common demoninator in order to fit them into your equations and how to find the answer.
How To: Calculate probability in "at least one" problems
Calculating probablities can be used to help us make decision. PatrickJMT explains how to calculate probability in an "either A or not A" scenario. The probability of A plus the probability of not A is equal to one. Therefore, the probability of A is equal to one minus the probability of not A ; P(A)= 1 - P(not A). The probability of a major earthquake in San Francisco over a period of time is used as an example. The probablity of an earthquake of a magnitude of 7.5 or greater in San Francisc...
How To: Find the entire length of a segment using the midpoint
This video shows the method to find the length of the total segment using the midpoint. Let the total line segment be PS. Let Q be the midpoint of PS. Let R be a point on the line segment QS. The first step involves the use of midpoint to find out the length of QS. We are given that QR = 1 and RS = 4.5. QS is equal to QR plus RS which is equal to 5.5. Now since Q is the midpoint of PS the total length of the segment PS is equal to twice the length of the segment QS. This is equal to 11 units....
How To: Work with decimal numbers in prealgebra
You can do simple decimal calculation with out using a calculator once you understand the basic concept of decimals. In decimal equations when you have various operations between decimal numbers, you have to go by the order of operations in simplifying it. The order of operations states that you have to first divide, then multiply and at last add or subtract the remaining terms. You have to work the operations from left to right. Use a calculator only when you are required to multiply or divi...
How To: Change improper fractions into mixed numbers
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 change top-heavy improper fractions into mixed numbers.
How To: Graph linear equations using a table
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). With this free video math lesson, you'll learn how to graph a system of linear equations using a T-Chart.
How To: Find a percent of a number
Having trouble figuring out percentages? If so, you'd be well served to give this free math lesson 100% of your attention. After watching it, you'll be able to answer questions like, "What's 25% of 38?" or "What's 38% of 25?" For more information on calculating percentages with simple arithmetic, watch this free video guide.
How To: Use differentiation equations to solve for position
This video teaches how to use calculus find the position, velocity and acceleration of an object. Imagine an object moving on a straight line. It's position at any time (t) is given as s(t) pronounced "s of t". It's velocity is v(t)= s'(t) which is the derivative of s(t). It's acceleration a(t) is the derivative of its velocity v'(t). If we look at it from a different perspective we are differentiating. The derivative of the position is its velocity, the derivative of its velocity is it accel...
How To: Find the average value of a function over an interval
When you have to find the average of two or five numbers then you have to add all the numbers and then divide then by two or five respectively. However in the case of the function you have infinite many values over any interval. But it is not possible to add all and then divide by infinity. Therefore you have to calculate in a different way. Imagine that you have to find the average of y=f(x). Then you have to average it from the interval from ‘a’ to ‘b’. The inner area under the curve shall ...
How To: Approximate the area under a curve using rectangles
The idea of finding the area under a curve is an important fundamental concept in calculus. Consider a function y = f(x). Now the area under the curve is to be calculated. The area under a curve problem is stated as 'Let f(x) be non negative on [a, b]. Find the area of the region lying beneath the curve y = f(x) and above the x-axes, from x = a to x = b. Note that finding the area under a curve will imply that you are dealing with a non negative function. The way to approach is to divide the ...
How To: Use a formula to find the area of a parallelogram
This video shows us how to use a formula to find the area of a parallelogram. The formula for finding the area of parallelogram is the same as finding the area of rectangle or a square which is equal to length time’s breadth. But the parallelogram looks a bit different and the parallelogram is basically a rectangle but it is not at right angles. If you draw two altitudes then it is a rectangle with two triangles and if you cut one of the triangles and paste it next to another triangle then we...
How To: Solve complex indefinite integrals in calculus
In this video the math teacher explains the meaning of the indefinite integral formula in calculus by stating it in terms of antiderivatives. He then shows in general terms how this indefinite integral formula has a related derivative formula, i.e. if the derivative of F(x) is f(x) then the indefinite integral of f(x) is F(x) plus a constant term (C). With this general relationship the teacher takes us through three related examples where he converts a derivative formula to an integral formul...
How To: Use differential equations to represent growth
This video shows the method to use differential equations to represent growth. Consider the function y=multiple of C & e raised to kx or Ce^(kx). Differentiating it with respect to x, we get dy/dx=kCe^(kx) or ky. So, the solution of the differential equation dy/dx=ky is Ce^(kx). There are two possibilities in the function y=e^(kx). It can be exponentially growth or decay function. This depends on the value of k. If k is greater than 0 or k>0, we get an exponential growth function. On the othe...
How To: Antidifferentiate functions with radicals in calculus
This video demonstrates how to do anti-differentiate functions with radicals in calculus. To simply problems, try to substitute. For example, in the problem, the integral of x times the square root of x plus 2 dx. You can substitute w for everything underneath the radical: i.e. x + 2. When you simplify, it becomes: the integral of x times the square root of w dw. Now, you need to get rid of the x, which you can do with a substitution: w – 2 = x. Now, plug in the values and simplify it.
How To: Find the graph of a square root function
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). With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to sketch the graph a square root function.
How To: Use the quadratic formula on a graphing calculator
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). With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to work with the quadratic formula on your graphing calculator.
How To: Divide decimal numbers by whole numbers in basic math
Your first step is to bring your decimal point up to the top of the equation. The you divide the whole number into the decimal number. In this instance, 5 into 1.25. 5 goes into 1 0 times, so you put the zero in the first space. 5 goes into 12 twice, so you place a 2 up top, after the decimal. Then you subtract 10 from the 12 to leave you with a 2. This then gets added on to the 5, so you divide 2 into 25 giving you 5. So your answer is 0.15. You can then do this for any whole number and frac...
How To: Rationalize a denominator
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). With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to rationalize a denominator.
How To: Make calculations with the Pythagorean theorem
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). With this installment from Internet pedagogical superstar Salman Khan's series of free math tutorials, you'll learn how to solve problems with the Pythagorean theorem in geometry.
How To: Solve a complicated radical 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 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 solve a complex radical equation in algebra.