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How To: Solve a system of equations with the comparison method

In this video tutorial the instructor shows how to solve equations by the comparison method. In this method he isolates either the x or y variables in both the equations and now compares the other side of equations directly to derive the value of the other variable. Now this derived value of the variable can be used by substituting it in one of the original variables to derive the value of the other variable. He goes on and shows how to do this with an example by solving it. This video gives ...

How To: Find the area of complex figures

In this tutorial the author explains how to compute the area of a complex figure. Now he first defines what a complex figure is by saying that a complex figure is a figure made up of two or more basic shapes. He uses an example to convey his idea and breaks that sample figure into basic squares and rectangles. Now he computes the areas of these individual units separately and finally puts them together to arrive at the final area of the complex figure. If you are looking to compute the area o...

How To: Find the common ratio of a geometric series

Interested in knowing how to find the ratio of a geometric series? 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: Convert improper fractions to mixed numbers quickly

Watch this video to learn how to convert improper fractions to mixed numbers. For example, follow these steps. First step is one fraction value. For example 7/3. Second step is divide the numerator by denominator means when 7 divide 3 you can get remainder as 1. Means 7 before value can multiply with the 6 so you can subtract 7-6=1 that is remainder. Multiplied value of 3 nothing but 2 is multiplication of the mixed numbers remainder take it as a numerator and denominator is always take it as...

How To: Find points of intersection in different equations

In this tutorial the instructor shows how to solve linear and quadratic equations. It is a liner quadratic system where he shows a parabola and a straight line and he intends to solve the points where the line intersects the parabola. Now he uses comparison to compare the values of y in both the equation resulting in a equation in x. Now he shows the factors of the obtained polynomial equation and there by finding the values of x coordinates. Now he substitutes these values of x in the origin...

How To: Find percent by mass & percent composition

In chemistry you come across problems which ask you to find the percent by mass and percent composition of each element in a chemical compound. To do this the first step is to compute the molar mass. Use the periodic table to look up the mass of individual atoms and multiply it by the number of atoms to find the mass of that element. Now add up all the masses to arrive at the molar mass of the compound. Now to find the percent composition of an element divide the total mass of each element by...

How To: Draw a reflection in Geometry

In this tutorial the author shows how to draw reflections in geometry. He shows how to draw them with a couple of examples in which he uses a reflection line and an object whose image is to be reflected. Now he draws perpendicular lines to the reflection line from the vertex of the original figure. He draws similar lines to all the vertexes all of same length and now after joining the ends of those lines a reflection of the original figure is obtained. This video shows a step by step method t...

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...

How To: Figure out a tip without a calculator

To figure out a tip without a calculator, first remove the pennies amount in the bill. For example, if your bill is $23.76 becomes $23.70. To figure out a 10% tip, move the decimal point one place to the left. So, 23.70 becomes 2.370 or $2.37. Bump up that number to $2.30 or $2.40 or $2.50 cents, depending on your preference. Since 20% equals two times 10%, double the figure you computed for 10%. So, $2.30 becomes $4.60, or $2.40 becomes $4.80 or $2.50 becomes $5.00. Using this method, you wo...

How To: Divide a two-digit number into a three-digit number

With this free video math lesson, you'll learn how to do long division with double and triple-digit numbers. With mathematics, as with anything else, not everyone progresses at the same rate. Basic math 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.

How To: Find the percentage of a number easily

In this arithmetic basics tutorial the author shows how to find the percentage of a number. He says that hundred percentage of number is the same number. He says that if we find the percentage of a number where the percentage is less that 100, then the value of the number reduces. Similarly if we find the percentage of a number where the percentage is more than 100, then the value will be more than the original number. He says that to find the percentage of a number we need to mark a decimal ...

How To: Solve problems involving deductive reasoning

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 unpack and solve word problems that require you to apply deductive reasoning.

How To: Estimate probabilities with the empirical rule

Learn how to use the empirical rule (or 68-95-99.7 rule) to estimate probabilities for normal distributions in statistics. 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 fre...

How To: Perform short division

In this Education video tutorial you will learn how to perform short division. The first example is a division by a single digit; 741 divided by 3. You write it as shown in the video and start dividing from the left digit. So, 7 divided by 3 will give 2 with 1 as remainder. Write this down as demonstrated in the video. 1 and 4 make 14 and dividing 14 by3 will give 4 and remainder is 2. Now dividing 2 and 1, that is 21 by 3 you get 7. The answer is 247. The next example is 847 divided by 5. 8 ...

How To: Derive the equation of a straight line

In this tutorial the instructor shows how to derive a straight line equation. He shows us a process that consists of two steps. In step one he uses the slope formula to obtain the slope of the line which is the ratio of difference of y-coordinates and difference of x-coordinates. Now in the step two he uses the slope he obtained in the first step and equates it two a another slope derivation which uses a generic x, y variables and a real point. Now solving this equation he arrives at the equa...

How To: Simplify exponential expressions via the quotient rule

This video demonstrates the quotient rule as applied to exponential expressions that appear in the form of, to use the word loosely, a fraction. The name, "quotient rule", refers to the fact that it applies to expressions which are divided by other expressions. The video begins by explaining that the quotient rule allows expressions in this form to be simplified if they contain like bases (i.e., the terms are of the same variable). The quotient rule allows the expression to be simplified by s...

How To: Solve inverse proportions

This video tutorial shows how to solve inverse proportions. The tutor says that in inverse proportion it works differently than in the direct proportion. He says that in inverse proportion more means less or less means more. He uses the example of driving a car to illustrate his idea. He says that if you drive a car with more speed, you take less time to reach a place i.e. here more speed means less time. He goes on and solves a problem involving inverse proportion explaining how to solve the...

How To: Find the complex conjugate of a 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: Perform long division

Having trouble with long division?? This educational instruction video will teach you how to correctly perform long division. The easy to follow steps will teach you the right technique and you will be able to solve those pesky long division problems in a flash. So if you want to improve your math skills or you just want to learn how to perform long division, watch this easy to follow instructional video that will teach you the simple way of tackling long division problems.

How To: Plot a real number on a number line

This video tells you how to plot a real number on a number line. For example consider -3.1. You know -3.1 lies between -3 and -4. You also know -3.1 lies very close or next to 3. So all you have to do is, put a point just before -3. Now you have marked -3.1 on a number line. Similarly you can point any real number on a number line. It is quite an easy job to plot real numbers on a number line.

How To: Graph linear equations using y=mx+b

This video is an instructional guide about Graph Linear Equations presented in algebraic form. It is an easy to follow, step by step guide to solving such equations using the graph intercept formula. The first example equation is Y = 2x -1 over y = mx + b. The video then shows you how to breakdown the equation into manageable sums using fractions to represent the data, and then presents the formula for interpreting the answer from these sums onto the graph co-ordinates. The second and third e...

How To: Solve temperature subtraction problems (integers)

An educational video from free math tutoring that shows an easy way to calculate differences of temperature. Many times people commit simple mistakes in subtracting temperatures that lead to illogical results. This video explains a very common pitfall and at the same time, clears up an important concept in temperature subtraction.

How To: Calculate the circumference of a circle

This video shows how to calculate the circumference of a given circle. The video first describes the circumference or perimeter of a circle as the distance around the outside of a circle. To find the circumference we need either the radius or the diameter of the circle. When you know the diameter of the circle, the formula to find the circumference denoted by 'C' is 'pi' times the diameter, where 'd' is the diameter and 'pi' is a constant, the approximate value being 3.14. And when you are gi...

How To: Convert decimals into fractions

In this simple tutorial the author shows the basic arithmetic operations like converting a terminating decimal into a fraction. He says that the complexity depends up on the number we are converting. He asks us to imagine the decimal as a fraction with an imaginary denominator of value one. Now he intends to remove the decimal in the numerator by moving it to the right of the number and he tells us to similarly move similar number of decimal places in the denominator to maintain the original ...

How To: Solve angle problems in geometry

Need some help figuring out how to work with angles in geometry? Look no further. 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 sol...

How To: Find real and imaginary parts of a 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: Derive and use the slope formula

In this video, we learn how to derive and use the slop formula. The slope of a line is equal to change in y divided by the change in x. First, put the first point on the coordinate point. Then, represent the X and Y by X1 and Y1. Then, put the second point on the plane, representing the coordinates with X2 and Y2. Now, with these two points, draw a straight line and derive the formula from here. The change in X will be from X1 to X2. Now, replace that with the change in X and do the same for ...

How To: Subtract fractions with borrowing

This how-to video describes how to subtract fractions using the borrowing method. The video shows viewers everything they need to know including basic subtraction of fractions, how to find common denominators, to the more difficult borrowing techniques. The narrator in this video does a great job of keeping things simple enough for anybody to understand. At the same time, he goes in depth enough that you really get how to use this technique. The voice in this video is very calm and clear. Thi...

How To: Graph a quadratic function in factored form

This video deals with solving quadratic functions. It does not involve the use of the quadratic equation; rather, only factored equations are used. The speaker starts out with a factored quadratic equation. The speaker goes on to do the mathematical steps necessary to find both the x and y intercepts of the quadratic function at hand. The author then continues on with the example to find the function's minimum. Next all of the points that have been solved for are plotted and the function is s...

How To: Reduce a fraction to its simplest form in basic math

Fractions are numbers of the form a/b, where a and b are integers. Fractions are also called as ratios. Fractions are further divided into proper fractions and improper fractions. Proper fractions are those where the numerator is less than the denominator and improper fractions are those where the numerator is greater than the denominator. As fractions are ratios a fraction can have many equivalent forms. Multiplying the numerator and denominator of a fraction with a same number gives a fract...

How To: Figure out the domain of a vector function

Need to know how to calculate the domain of a vector-valued 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: Draw a right trapezoid in Geometry

Watch this video to learn how to draw a right trapezoid using given specifications for lengths of sides. A right trapezoid is a four-sided shape with two right angles and two parallel sides. First, draw the long base. Then draw a 90 degree angle at one end of the base, using a protractor. Mark the angle to show it is 90 degrees. Then draw another 90 degree angle at the top. This is the first video in a set--to finish learning you must watch the next segment. If you watch these videos you will...