Hot Education Posts
How To: Subtract mixed numbers with borrowing
This video teaches you to subtract mixed numbers with borrowing. Consider 2 mixed numbers. For example 8 and 2/7 and the other 5 and 4/5.You have to subtract 5 and 4/5 from 8 and 2/7. First you have to convert the fractions to their common denominator. To equate the denominators of these two fractions you have to multiply the first denominator with the numerator and the denominator of the second fraction and also multiply the numerator and denominator of the first fraction with the denominato...
How To: Make a permanent, reusable glow stick
Make a reusable glow stick, glow-in-the-dark-style! Imagine, you'll never have to buy one of those ChemLite's again, because you can reuse this homemade glow stick over and over again. This video tutorial will show you how to make a permanent, reusable glow stick. The materials in this experiment are simple: epoxy resin, straw, and some phosphor powder.
How To: Make Your Own Homemade Glow Sticks
Glow sticks, a popular favor at parties and outdoor events, and a must-have on Halloween, can be traced back to the United States Navy in the mid-1960s. The military desired improved visibility during night operations, and glow sticks, with their small-size portability and lack of batteries, were a perfect tactical solution.
How To: Find the area of a circle when you know the diameter
In this video, it is shown how to calculate the area of a circle where the diameter is given. The formula for calculating the area of a circle is pi multiplied by square of radius. Radius is actually half of the diameter. In this video, the diameter is given as 10.6 meters. Hence, the radius will be half of 10.6 which is equal to 5.3 meters. Now, to find the area we shall multiply pi with the square of 5.3. Square of 5.3 is 28.09. If we multiply 28.09 with pi we shall get the area of the circ...
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: Find the equation of a line given 2 points
This tutorial teaches you how to find a mathematical equation of a line given 2 points that exists on the line. The tutorial starts off with 2 points labeled (2,-4) and (3,6). The first step is to determine the slope of the line using the formula given in the tutorial in blue. The slope is then solved as 'm'. Plug the slope and the points into another formula given in green. The tutorial maker provides a tip that one can use x1 and y1 or x2 and y2, however, it must be consistent. After, solve...
How To: Find the Percent Given Two Numbers
Whether you're shopping for deals, need help with a little math, or any number of other occasions, it's a valuable skill to know how to quickly figure out a percentage given two numbers.
How To: Calculate the area of a parallelogram
Calculating The Area Of A Parallelogram A parallelogram is a 4-sided shape formed by two pairs of parallel lines. Opposite sides are equal in length and opposite angles are equal in measure. To find the area of a parallelogram, multiply the base by the height. The formula is:
How To: Add and subtract variables
Math Problem Generator gives a video about how to add and subtract variables. All you have to do is combine the coefficient, which is the number that comes before the variable. The numbers are added or subtracted but the variable remains the same. In the video, the example given is 9x + 6x - x. First you add 9x + 6x, giving you 15x. The equation is now 15x - x. If a variable has no number written in front of it, that means the value is 1. So the equation is 15x - 1x and that is equal to 14x.
How To: Find the surface area of a cylinder easily
In this video tutorial the author shows how to find the surface area of a cylinder. He shows a four step approach to solve this problem. First he gives us a formula to find the surface area of a cylinder, where Surface area A = 2 * Pi * R * R + 2 * Pi * R * H, where R is the radius of the base of the cylinder and H is the height of the cylinder. Now he identifies those values and substitutes them in the formula giving the surface area of the cylinder. This video shows how to compute the surfa...
How To: Make Black Snake Fireworks With & Without Fire
In this video, I'll be showing you how classic black snakes work and how to make them at home. There are actually two methods covered in the video — one that uses fire and one that does not. So just choose the one that fits best for your situation.
How To: Make chlorine gas with pool chlorine and hydrochloric acid
Chlorine gas is a very useful oxidant, which was first introduced as a toxic weapon by the German Army. Even today, it's still used as a weapon, most recently in the Iraq War by insurgents. But chlorine gas has more useful (and less lethal) applications, and if you want to learn how to make some at home, NurdRage has the answers.
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: Build a catapult out of rubber bands & a wire hanger
In this tutorial, we learn how to build a catapult out of rubber bands & a wire hanger. To do this, you will first need: one wire hanger, plastic spoon, rubber bands, small marshmallows, and measuring tape. Now, hold your hand in the center of the hanger and pull up both sides around it. After this, fold back the front for balance and straighten it up so it's stable. Next, you will take one rubber band and put it around the sides. Then, take the spoon and put it in between the rubber band and...
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: Explore Density, Viscosity & Miscibility with a Colorful Layered Liquid Science Experiment
Ever wonder why Jupiter has those colored bands across its surface? Jupiter's enormous mass is made from an array of different liquids, and those fluids do not play well together because of their different makeup. All of the hydrogen- and helium-based fluids are thought not to be miscible, which means that they aren't homogeneous in nature, resulting in strikingly beautiful bands across the planet's surface. But what about viscosity and how that correlates to the development of planets? What ...
How To: Solve word problems containing radical equations
See how to unpack and solve a word problem containing radical equations with this free video math lesson from Internet pedagogical superstar Simon Khan. 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: Make Ammonium Nitrate with NaHSO4 and Nitrate Salt
OK, so you don't necessarily have to make ammonium nitrate to have ammonium nitrate — ammonium nitrate can simply be obtained from fertilizers and instant cold packs. Making homemade NH4NO3 can be much more expensive then buying it, but this method is not meant to be a viable route, it's an exploration of science and chemistry.
How To: Use and find x & y-intercepts in algebra
A straight line can be represented in the form of a liner equation containing two variables x and y. When the equation is graphed on a pair of coordinate axes, the line passes cut through the axes in two points. The point where the line cuts the x-axes is called as its x coordinate and the point where the line cuts the y-axes is called as its y coordinate. In this way a line has x-intercept and y-intercept. The x-intercept of a line lies on x axes and is in the form (a,0). Similarly the y-int...
How To: Handle missing terms in algebraic long division
In this tutorial you are shown exactly how to do algebraic long division when terms are missing in the polynomial. Follow these steps and you can divide whatever you'd like:
Use the quadratic equation: finding the mirror point
In this video the tutor shows how to find the mirror point using a quadratic equation. He says that to graph a parabola you need to find the mirror point symmetrical to the Y-intercept. Now he explains how to find a mirror point using an example with sample values. He begins with saying that the Y-coordinate of the mirror point is same as the Y-coordinate of the Y-intercept. Now you have to find the x coordinate of the mirror point which he shows that it is double the x-coordinate of the vert...
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: Find a missing side of a triangle, similar to another
In this tutorial the author shows how to find out the missing side of a triangle which is similar to an other triangle. He explains the concept of similar triangle using diagrams and by showing that similar triangles have equal corresponding angles and parallel sides. Now he labels sides of similar triangles and intends to find out the length of unknown side. Now in similar triangles, as the lengths of sides are proportionate he shows how to write a equation of proportion and solve it finding...
How To: Solve for the missing ratios or proportions
In this video the tutor shows how to solve the missing ratios or proportions. He explains it with an example, where a number in one of the ratios is missing and he intends to find this value. He shows the example of cross multiplication, where you multiply the values on the either side of the equation diagonally and finally solves the equation which results in the value of the unknown value. This is an introductory video explaining how to use rations and proportions to find missing values.
How To: Solve for X (advanced)
The video describes how to find 'x' in the algebraic equation -3x + 7x - 6 = 30
How To: Make aluminum nitrate nonahydrate
Aluminum nitrate nonahydrate is a crystalline hydrate - a salt of aluminum and nitric acid - Al(NO3)3·9H2O. It's used for a variety of things such as antiperspirants, corrosion inhibitors, and petroleum refining, or… glow-in-the-dark powder. Watch this science video tutorial from Nurd Rage on how to make aluminum nitrate nonahydrate with Dr. Lithium.
News: Reverse Arrow Trick - Amazing
When the arrow is moved to a particular distance behind the glass, it looks like it reversed itself. When light passes from one material to another, it can bend or refract. In the experiment that you just completed, light traveled from the air, through the glass, through the water, through the back of the glass, and then back through the air, before hitting the arrow. Anytime that light passes from one medium, or material, into another, it refracts.
How To: Make Copper Glow Red Hot with Acetone
In this video, I will show you how to make copper glow red hot with the catalytic oxidation of acetone. For this science experiment, we'll just need some acetone, copper wire, and a flame source to initially heat the copper coil we'll make.
How To: Lift fingerprints from a bottle of water with super glue
Does someone keep drinking part of water bottle and leaving them around your house or office, taunting you with their wastefulness? Thanks to forensic technology, it is possible to catch the culprit with easy household materials. This video will show you how to use super glue to lift fingerprints off of a water bottle where normal fingerprint-lifting technology would not be sufficient. Plus, you get to use a heat gun! Always fun.
How To: Perform 10 awesome science magic party tricks
The best part of science class for many was the awesome demonstrations and experiments teachers use to demonstrate scientific principles. This video will teach you how to capture some of that magic by performing ten awesome science party / magic tricks, like relighting a match with smoke and rolling a can around on it's rim.
How To: Factor trinomials using the Berry factoring method
In this free video math lesson YAY MATH, we learn how to factor trionmials using the Berry method. With mathematics, as with anything else, not everyone progresses at the same rate. Algebra is no exception. 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. Whether you need help finishing your homework or studying for that next...
How To: Make ammonium chloride from hydrochloric acid and ammonia
This free video science lesson from the Home Scientist demonstrates a simple technique for creating ammonium chloride from hydrochloric acid and ammonia. For all of the relevant details and detailed, step-by-step instructions, as well as to get started trying this experiment yourself, watch this home-science how-to.
How To: Divide numbers with exponents
In this tutorial, we learn how to divide numbers with exponents. The quotient rule states that we can divide two powers with the same base by subtracting the exponents. With the same base, you can subtract the exponents to get something that would be the answer. For example, if you have 6(to the fourth) divided by 6(to the second), this would come to equal 6(to 4-2). This would break down to equal 6(to the second power). Once you have this, you will be able to do the math for this and figure ...
How To: Evaluate a line integral along a straight line segment
This video tutorial is in the Education category which will show you how to evaluate a line integral along a straight line segment using the definition of the line integral. This video evaluates a line integral along a straight line segment using a parametric representation of the curve (using a vector representation of the line segment) and then integrating. A vector representation of a line that starts at r0 and ends at r1 is r(t) = (1-t)r0 + tr1 where t is greater than equal to 0 and lesse...
News: Jane Goodall Was a Babe (and One of History's Greatest Conservationists)
National Geographic recently published a retrospective of the lovely Jane Goodall, one of the world's most accomplished conservationists. The feature includes every image of Goodall to ever appear in the magazine for the past fifty years.
How To: Convert Fahrenheit to Celsius with a formula
In order to convert Celsius to Fahrenheit, you will need to use this formula: F = 9/5C + 32. Therefore, you will need to solve for C or substitute values and solve in that manner.
How To: Add and subtract rational expressions in algebra
Need help adding and subtracting rational expressions in algebra? Grab a pen and hunker down with these practice problems. 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 a 2x2 system of linear equations with inverses
See how to solve a two-by-two system of linear equations using inverses (derived from determinants). 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: Use matrices to solve systems of equations on a TI83
This video shows how to use matrices to solve systems of linear equations on TI83 and TI84 series graphing calculators. 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 volume of a cylinder
Need help calculating the volume of a cylinder? It's easy! So easy, in fact, that a complete and thorough overview of the process can be presented in forty-five seconds' time. Study for your next geometry test or just finish your homework with this free video math lesson, which demonstrates how to find the volume of a cylinder using v=pr^2h.