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How To: Change Fahrenheit to Celsius

This video is a tutorial on how to convert Celsius to Fahrenheit. The title of the film says it will teach you how to convert Fahrenheit to Celsius, but it does not. It does just the opposite. The video begins by comparing Fahrenheit and Celsius. He points out that Fahrenheit measures water to freeze at 32 and water to boil at 212. Celsius measures water to freeze at 0 and water to boil at 100. To convert Celsius to Fahrenheit, multiply the Celsius temperature by 1.8 and add 32. Many countrie...

How To: Use a TI-89 to calculate nCr

This video shows you how to do a mathematical representation on computing the nCr function using a TI-89 calculator. You can write the nCr notation in different forms. It can be simplified from nCr to C(n,r). The symbol can either be read "n choose r" or "n taken r at a time" which are from it's probability applications. On the example to find "26 choose 17", go to the Home screen of the TI-89 calculator and then go 2nd 5 which is Math. Go choose probability and then to nCr to type in (26,17)...

How To: Find a slope of a line parallel/perpendicular to it

This video tells you how to find a slope of a parallel / perpendicular to it. In the equation y = mx + c, m is the slope. To calculate the slope of a line that is parallel to another line, you have to consider the rule m1 = m2 which means slope of the first line m1 is equal to the second line m2, if both the lines are parallel. Take the equation y = 2/3x - 7.2/3 is the slope. According to the rule m1 = 2/3 and so m2 = 2/3.Now to calculate the slope of perpendicular line you have another rule ...

How To: Find the 100th term in a sequence

Need to find the nth term in a given arithmetic sequence? 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 pedagogical superstar Salman Khan's seri...

How To: Know if matrices can be multiplied

In this Education video tutorial you will learn how to know if matrices can be multiplied. If the column of the first and the row of the second match, you can multiply them. For example if, matrix A has 2 rows and 3 columns (A: 2x3) and matrix B has 3 rows and 4 columns (B: 3x4), then you can multiply them. But, if A: 3x2 and B: 3x4, you cannot multiply them. The shape of the resultant matrix will be the shape of the outer numbers. For example, we saw that if A:2x3 and B :3x2, then they can b...

How To: Divide small numbers by big numbers

This is a mathematical educational video on how to divide a small number by a larger number. You are aware that it is easy to divide a larger number by a small number. For example, if you want to divide 379 by 9 it is easy to do so. But if you have to divide 9 by 379 it is a bit difficult. You have to add a zero and see if you can divide. You need to add one more zero so that you can divide 900 by 379. But you should know that the answer would start like this 0.0 as we have added 2 zeros alre...

How To: Factor quadratic expressions using trial and error

Sometimes there's no better way to factor a quadratic equation than by simple brute-force trial and error. Watch this free video algebra lesson to see how it's done. 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: Write a slope-intercept equation given an X-Y table

In this tutorial the author shows how to derive a slope-intercept equation of a line given an X-Y table. He explains that the general form of slope intercept form which is y = m*x + b. Now he intends to find value of slope, i.e. m first. Now slope is change in y over change in x. He computes the slope using the X-Y values from the table. Next he substitutes a pair of x, y value in the equation to compute the value of y intercept b. Now finally substituting the values in the equation the slop-...

How To: Factor the sum and difference of cubes

Need to know how to factor the sum or difference of two cubes? 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 study for that next big test).

How To: Cancel out in basic algebra

This video gives you brief tutorial on simplifying expressions, or canceling out common factors. He starts out by answering the question "What is canceling?" and demonstrates a basic example. You find the greatest common factor between the numerator and denominator, which you then divide both by. This can also be done if you have variables in your fraction. He then shows it can be done the same way if you have binomials in your fractions. However, you must be careful that the denominator does...

How To: Square expressions involving radicals

Here we look at squaring expressions that involve radicals because people tend to make some common mistakes while solving such expressions. Take 5 times the square root of y quantity squared, the answer here is not 5y. Here's the reason, square means to multiply something with itself so the square of 5 root y would be 5 root y into 5 root y. So 5 x 5 is 25 and under root y into under root y equals just y so the answer will be 25y.

How To: Simplify a complex fraction w/ binomial denominators

To simplify a complex fraction, turn it into one fraction on the top divided into a fraction on the bottom. Once this is complete, you will turn the division into the two into a multiple by the reciprocal, factor, and then cancel. To make a division, find the lowest common denominator of both the top and the bottom. Once you get this division equation, look carefully at the equations. If something can be easily canceled, go ahead and cancel it out at this time. If you cannot cancel anything a...

How To: Calculate percentage

Not sure exactly how to calculate a twenty percent tip for your waitress? Or how about how to figure out how much less your cost will be with that thirty percent off tag? Use these steps to calculate percentage, without a calculator.

How To: Express inequalities using interval notation

With all the subjects offered in junior high and high school, math isn't a favorite for many. It can often times be confusing and although the results are concrete and don't require anybody to be imaginative, it can still pose a problem. In this tutorial, you'll find out how to express inequalities using interval notation. Good luck and enjoy!

How To: Clear fractions from linear equations in Algebra

Need help figuring out how to remove fractions from linear equations in algebra? 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: Remember "greater than" & "less than" symbols

This video shows you how to easily remember "greater than" and "less than" math symbols. The first thing you have to remember is that "less than" symbol looks like the letter L ("less than" symbol is "<"). When you see this sign, remember that < looks like L and means "less than". The other symbol, "greater than" does not look like the letter L, therefore it cannot be "less than" and it's easier to remember. The "greater than" symbol is ">". That's it! Good Luck!

How To: Calculate percent error in chemistry lab activities

If you want to know how to calculate percent error easily, you should watch this video. Error is the amount of deviation from accurate values. Error calculation is not possible, unless you make a quantitative measurement of the various quantities involved in your experiment. Measurement can help us in calculating errors and knowing how right we are in our theoretical models. In calculating percent error, We need to get the experimental value and the value which you are aiming at, which is the...

How To: Calculate percent yield

This video shows you how to calculate the percentage yield in chemistry. To find the percentage yield, you will need to divide the actual yield by the theoretical yield. Then, multiply it by 100: i.e. % yield = actual yield/theoretical yield x 100. An actual yield is the amount of a substance produced in an actual laboratory experiment. It is based on an actual physical measurement of a quantity. The theoretical yield is the yield as is calculated on paper: i.e. through calculations. Therefor...

How To: Solve operations on rational functions (f o g)(x)

YAYMATH In order to use rational functions in intermediate algebra, Robert Ahdoot begins by setting values to the functions f(x) and g(x). He then adds these functions together, with the equation (f+g)(x). After addition comes subtraction, using the equation (f-g)(x). And finally multiplication, which is (ftimesg)(x). This is a little more complicated, requiring distribution of a binomial across a polynomial, but it's clearly demonstrated and explained. This video explains what to do with add...

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 vertices of a polygon of constraints

In this tutorial the instructor shows how to find the vertices of a polygon of constraints. In any optimization problem after defining your polygon you need to find its vertices. First you will have a set of equations which represents the constraints in your problem. Now you have to find the coordinates of the vertex of it by solving the optimization problem. To do that you have to start with a point and check the lines that are passing through it. Now take those lines and solve them for the ...

How To: Convert recurring decimals to fractions

In this video we learn how to convert recurring decimals to fractions. Start off by writing out the decimal with the dot next to it to show that it's recurring. This means that the number goes on forever and doesn't stop. To convert this to a fraction, write down the number as the numerator. On the bottom you will put the number 9 always. Now, you can divide these two numbers with each other using a calculator. Once you do this, you will get the correct answer. Once you divide it out, you wil...

How To: Write and graph an equation in slope intercept form

This video teaches us the method to write an equation in slope intercept form and to graph it. The equation of line is y = mx + c. m is the slope and c is the y intercept or the point where it crosses the y axis. Let us find the equation of line if it crosses (8,6) and m=1/2. Substituting the values of x,y and m we get 6=(8)(1/2)+b. Simplifying we get b=2. Substituting the values in the equation of line, we get y = m/2 + 2. Suppose we want to find the x coordinate of a point on the line given...

How To: Find the length of a segment using the midpoint II

First of all in the given question you have to write down the values of the total length of the line segment, PS=15. The length of the line segment, QR =3. Now you have to find the value of line segment RS. Because you know that the Q is the midpoint of the line segments PQ and QS must be equal. Therefore you can find out the length of the half of the segment using the midpoint. Subtract the value of QR from QS. Given that segment PS=15 and Q is the midpoint, you can conclude segment PQ=7.5 a...

How To: Determine the age of a fossil using carbon-14

If you have a fossil, you can tell how old it is by the carbon 14 dating method. This is a formula which helps you to date a fossil by its carbon. If a fossil contains 60% of its original carbon, how old is the fossil? The half life of carbon 14 is 5600 years. That means this is how long it takes for half the nuclei to decay. After 5600 years, if we start with a gram, we end up with half a gram. This rather complex formula shows you how to solve this puzzle using accepted scientific methods.

How To: Find the x & y intercepts of rational functions

In this tutorial the instructor shows how to find the x and y intercepts of rational functions. Finding the intercepts of a rational function is similar to finding the intercepts of other normal equations. You can find the x intercept of the equation by setting the value of y to zero and solving the equation. Similarly you can solve the y intercept by setting the value of x to zero and solving the equation. Now while solving this rational function for intercepts if you face a situation where ...

How To: Convert temperature using y = mx + b

In this video the instructor shows how to do temperature conversions using y = m*x + b. Now if Celsius is represented by the variable C and Fahrenheit is represented by the symbol F, you can replace then in the previous equation in place of the variables x and y giving you the equation C = m*F + b. Now to solve for the values of the constants m and b you need to have values of two sample temperatures in both Celsius and Fahrenheit. Take the first sample and substitute in the above equation gi...

How To: Calculate azimuth in trigonometry

Azimuth is simply the angle of an object in the sky along the horizon. Yes, it's spherical trigonometry but it's not difficult! Check out this video and in just a few minutes you will be able to solve azimuth problems on your own.

How To: Find the area of an oblique triangle using formulas

In this tutorial the instructor shows how to find the area of an oblique triangle using different formulas. To find the area of an oblique triangle there are different formulae. The first formula to calculate the area of a triangle is area A = (1/2) * a * b * Sin(C), where a and b are the lengths of the two sides of the triangle and C is the value of the angle of the triangle that lies in between the two sides a, b. Now substitute these values in the given formula to find the area if you have...

How To: Do Celsius to Fahrenheit temperature conversion

The video teaches how to convert degrees Celsius to degrees Fahrenheit. First the boiling points of 32 degrees Fahrenheit and 100 degrees Celsius are plotted on the Y and X axis. Then a line is drawn to join them both. The value m is delta Y (boiling point minus freezing point, i.e., 212-32)/ delta X (boiling point minus freezing point, i.e., 100-0). So m works out to 180/100 or 1.8. Then the formula y=mx+b (intercept of y = 32) is used, substituting X with Celsius and y with Fahrenheit, to c...

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: Prove Rank(A) = Rank(transpose of A) in linear algebra

Learn how to prove that the rank of a matrix, A, is equal to the rank of its transpose in linear 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).

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: Do a rotation in Geometry

Learn how to do a rotation in geometry with this video! First step is to pout the pencil into the compass. Adjusting the pencil and compass needle is same. Suppose you want 165 degree size circle. Measure the reading with compass in protractor. Note the point and adjust the compass. After place the sharp end of the compass at the point and rotate the compass the circle will enabled. Next use protractor. We see 75 degree acute angle. Place the protractor on the line and mark the reading we wan...

How To: Do long multiplication

In this video the instructor gives you sample as of how to SLEP long multiplication. You start by breaking the numbers up to simpler forms. If you have a two digit number that your multiplying by a another two digit number you multiply the first two digit number and then buy the second digit of the second two digit number. You have to remember to carry the remainders. You then add your two multiplicative lines together giving you the sum. this can be done to cover any set of multi-digit numbe...