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How To: Solve 3 equations with 3 variables

You can solve 3 equations having 3 variables. Here are the 3 equation examples: x+2y+z=10. 2x-y+3z=-5. 2x-3y-5z=27. The goal is to reduce to 2 equations having 2 variables. Multiply bottom equation by (-1). Rewrite 2nd and 3rd equation. 2x-y+3z=-5. Add -2x+3y+5z+-27. Equals 2y+8z=-32. Go back to original equations and multiply by (-2). Then you have -2x -4-2z=-20. plus 2x -y +3z. When you add these 2 equations, the answer is -5y +z = -25. You have now reduced the equations from 3 equations do...

How To: Solve an equation for a specified variable

Need help wrapping your head around algebraic equations? Watch 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). With this guide, you'll learn how to solve algebraic equations containing variables.

How To: Find the volume of a cube, cylinder, pyramid or cone

This video shows the method to find the volume of a cube, cylinder, pyramid or cone. Volume is equal to the multiple of the area of the base and the height or V=(base area)(height). Starting with the cube, the volume= [(side)(side)](side) or side cube or side^3. In the video side=50m or V=125000 cubic centimeter. Volume of the cylinder= [(pi){(radius of base)^2}](height of cylinder) or V=(pi)(r^2)(h). Substituting the values, V=pi(2^2)(4) cubic inches or 16pi cubic inches. Volume of a pyramid...

How To: Use a protractor to measure an angle

This video in the Education category will show you how to use a protractor to measure an angle. This video is from Brightstorm. In Geometry it is important to know how to measure an angle. This is a very simple and easy process. In order to measure an angle, you will need a protractor. Every protractor has a base and a center point marked on the base. You will put the center point on the vertex of the angle. Then align the base line of the protractor perfectly on one side of the angle. Now ch...

How To: Solve rate-of-change problems with derivatives

Need to know how to use derivatives to solve rate-of-change problems? Find out. 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 solve...

How To: Calculate a limit at infinity with a radical

In this video, we learn how to calculate a limit at infinity with a radical. The idea is to take out the higher power of 'x' in the denominator first. If the x squared is under a radical, take that out so you're left with just 'x'. After this, divide every term by 'x'. Once you are finished with this, you can rewrite the equation. Next, you will use the rules of math to find the answer of the equation. This is hard math to do if you aren't used to it! Make sure you practice with the samples i...

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: Solve basic rate problems

Need some help figuring out a simple rate problem (involving the rate of a train for example? See how it's done with this free video math lesson. Need help finding the 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 peda...

How To: Factor & simplify different algebraic expressions

Math Made Easy offers some great SAT Test Prep. It helps you master the factoring and simplification of any kind of algebraic equation or expression. An expert math instructor provides easy to follow real-time chalkboard examples to help you work your way through step-by-step. It discusses when and when not to use the FOIL method. It demonstrates some of the most common factoring problems that you are likely to see on the SAT. With Math Made Easy, you don't have to let those trinomials scare ...

How To: Find velocity, acceleration, & distance by graphing

See how to calculate velocity from a distance time graph, how to calculate acceleration from a velocity time graph and how to calculate distance covered from a velocity time graph! 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 addition using the column addition method

Watch this math how to video and learn how to add using the column addition method. This simple addition method will help young students learn how to add. Use the column addition method to help with your homework or tutoring. Do addition using the column addition method.

How To: Remember how to divide fractions with a song

In this video tutorial the author shows how to divide fractions by singing the songs "I Can Divide". He sings a wonderful and funny song about how he is petrified about fractions and in the song somewhere he says that to divide just invert and multiply. He says that division of fractions is nothing but multiplication of the first fraction with the inverse of the second fraction. He shows this trick in a funny manner by singing a song which is very catchy with humorous lyrics. This video conta...

How To: Evaluate exponential expressions in algebra

Need some help figuring out how to solve exponential expressions in algebra? See how it's done 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: Factor perfect square polynomials

Learn how to factor perfect square polynomials and how to solve equations using the square root property. 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: Simplify complex fraction w/ single fraction on bottom

This is a great instructional video on education. This educational video teaches you how to simplify a complex fraction with a single fraction on bottom. Let us learn this with an example. Let us assume we have to simplify the complex fraction 5 by x-4 divided by 5-4x by 5. When you simplify this you will get 5-4x over x divided by 5-4x over 5. You will now get 5-4x over x multiplied by 5 over 5-4x. This is equal to 5 over x. This is how we have to simplify a complex fraction with a single fr...

How To: Solve a quadratic equation with a graphing calculator

This video walks you through the steps of solving quadratic equations with a graphing calculator. This excellent video shows you a clean blackboard, with the instructors voice showing exactly what to do. Don't fret, any question you may have, will be answered. Watching this video will make you feel like your back in the classroom but rather comfortably from your home.

How To: Divide fractions step by step

In this tutorial, we learn how to divide fractions step by step. First, you will need to know the different parts of the fraction, the numerator and the denominator. After you know these, you will flip the second fraction in the equation so the numerator is at the bottom and the denominator is at the top. Once you do this, change the division sign to a multiplication sign. Now, you will multiply the fraction as you normally do and then have the answer! This is a very simple way to divide frac...

How To: Shade a system of inequalities

In this video the instructor shows how to shade a system of inequalities. He says that shading a system of inequalities is similar to shading a single inequality but in the former case you tend to shade more than one inequality in the same graph. He shows how to do that using an example set of inequalities and plots the lines on the graph. He uses dotted lines for lesser than or greater than inequalities and uses straight lines for inequalities which contains the equal to symbol. Now he shade...

How To: Subtract fractions from a whole number

In order to subtract fractions from whole numbers you have to perform a few steps. First we have to borrow one from the whole number. So if you are subtracting 1/16 from 3, 3 becomes 2. Then you have to change the one you borrowed, so the 1 becomes 16 over 16 or 16/16 to match the common denominator in the fraction 1/16. So 16/16 - 1/16 = 15/16. Then you add the 2 that you had left after you borrowed the one from the whole number. The answer is 3 - 1/16 = 2 15/16.

How To: Find the volume of a rectangular prism

Another thing you will learn in geometry is volume. In this tutorial, learn how to find the correct volume of a rectangular prism. A rectangular prism is a three dimensional object, which is why you are searching for volume as opposed to area. Check out this video and see just how easy it is to calculate rectangular volume.

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: Calculate the area of a rhombus

This is how to calculate the area of a rhombus. A rhombus is a quadrilateral shape in which all sides are congruent. A rhombus has two sets of parallel lines, the diagonals of which form 90-degree angles at the point they meet. Also the angles opposite to one another are congruent. The area of a rhombus can be gotten by multiplying both the diagonals and then dividing the total by 2. Say one of the diagonals is 10 and the other is 12, the area will be 10 x 12 = 120/2 = 60. That is how to calc...

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

In this video the instructor shows how to find the slope of a line given two points that like on the line. Slope of a line is the measure of the steepness of the line compared to the angle made by the line with the x-axes. A line with positive slope slants forwards and a line with a negative slope slants backwards and a line parallel to x axes has zero slope. So if you are given two points (x1, y1) and (x2, y2), the slope of the line passing through those two points is equal to m = (y2 - y1)/...

How To: Solve circle-based problems in basic geometry

Need help figuring out how to work with circles in basic geometry? 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 about how to calculate an...

How To: Find the sine, cosine & tangent of an angle in trig

Need help figuring out the sine, cosine, and tangent of an angle in a right triangle? Need to know how to solve a matrix-form linear equation in algebra? Need help solving problems involving 45°-45°-90° right triangles? You're in luck. 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 stu...

How To: Change mixed numbers to improper fractions

In this Math tutorial, you will learn how to convert a mixed number into an improper fraction. The narrator explains the process in a very concise yet simple manner that will make math problems involving mixed numbers so much easier to solve. The general idea is to multiply the whole number with the denominator and then add that to the numerator. The explanation and illustration in the video makes it easy to understand.

How To: Calculate angles formed between parallel lines

Calculate the angles formed between parallel lines and a transversal. This free video geometry lesson will show you 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).

How To: Find the median & inter-quartile range

This video shows us the method to find the median and the inter-quartile range. The first step involves the arrangement of the numbers in the ascending order. Median is the middle number. The middle number is the number at (number of numbers + 1)/2 if the number of numbers is odd or the (number of number)/2 if the number of numbers is even. In the example the number is located at [(11+1)/2] or the 6th number. The inter-quartile range is higher quartile - lower quartile. The higher quartile is...

How To: Solve single-step equation by taking the reciprocal

In this video tutorial the instructor shows how to solve a single-step equation by taking the reciprocal. He says that in the equations of fractions containing a variable on the one side, you multiply the reciprocal of its numerical constant to it so that only the variable x stays out. Similarly we need to multiply the reciprocal value that we used on the left hand side on the right hand side too to maintain the equality. Now after simplification as only x is left on the one side we get its v...

How To: Write the square root of a negative complex number

Need a little help with your math homework? No problem, the Math Centre offers students video tutorials that will provide as a reference guide for self-study. Students get self-study resources targeted to the needs of individual courses, and teachers gain generic mathematics support and study materials for use with students.

How To: Find the volume of a regular pyramid

In this video, you will learn how to find the volume of a regular pyramid. Finding this volume is one of the basic steps in high school geometry. This tutorial will show you all of the steps and equations you need to solve this problem and soon you will be heading straight to the top of the class!

How To: Match exponential graphs

This video tutorial belongs to the Education category which is going to show you how to match exponential graphs. The video shows two graph sheets with three graphs marked A to F on each sheet and six equations. It starts off with matching the basic function, y = 2 to the power x. If you plug in zero for x, you get '2 to the power 0' which is 1. Hence, the equation becomes; y = 1. So, the graph that passes through y = 1 is the matching one. In the video it is graph A. You can watch the video ...