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Systems of Three Variables 2, Systems of Equations and Inequalities, Algebra II
Sal uses the elimination method to simplify a system of three variables. Next, he employs the substitution method to check his solution. This resource would nicely complement any lesson on this topic.
Khan Academy
Finding a Linear Equation Given a Point and Slope, Algebra Basics
When students are ready to use the slope and a coordinate pair to determine the equation of a line using slope-intercept form, then they will be ready to watch this video. Sal does a fantastic job explaining this concept.
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Consistent and Inconsistent Systems, Algebra II
First, Sal defines consistent and inconsistent equations. He then evaluates a system of linear equations to determine if they are consistent or not. This resource isobviousr and would be a wonderful video to show before a test or at an...
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Example 2: Factoring Quadratics by Grouping, Algebra I
Here is a complete and clear demonstration of the process needed to factor a trinomial with a non-1 leading coefficient. Sal uses various colors and provides working examples while he factors the simple trinomial. This video would be...
Khan Academy
Introduction to Graphing Systems of Linear Inequalities, Algebra II
If your class has a grasp on the concept of graphing systems of equations and has worked with inequalities, then it's time to expose them to the wonders of graphing systems of inequalities. Using various colors and a graph, Sal explains...
Khan Academy
Example 4: Factoring Quadratics as a Perfect Square of a Difference: (a-b)^2
Introduce young mathematicians to the concept of factoring trinomials with perfect squares. This descriptive video provides a meaningful explanation of the factoring process. Each step is carefully written out in various colors during...
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Polynomial Divided by Monomial, Polynomial and Rational Functions, Algebra I
Let's think about how a person could simplify an expression where a polynomial is divided by a monomial. Sal shares three different modes he could use to simplify, then uses each way to solve the same problem.
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Example 5: Adding Polynomials with Two Variables, Algebra I
While explaining how to add polynomial expressions with multiple variables, Sal uses academic vocabulary and a straightforward thinking process. This video is relatively short and would be appropriate for students working on homework or...
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Proper and Improper Fractions, Fractions, Pre-Algebra
Sal explains proper and improper fractions. He labels each part of the fractions using different colors. Note: This video is ideal for those who need a quick refresher on the definitions of proper and improper fractions. It is not a...
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Adding numbers with Different Signs (Example), Pre-Algebra
Explaining the concept of adding integers with different signs can become confusing. Use this video to provide students with a clear and explicit demonstration of how negative and positive numbers are added together. Sal uses a number...
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Example: Adding Two Digit Numbers (No Carrying)
Adding double-digit numbers can seem difficult for some students. But this Khan Academy video makes this process clear in a developmentally sound way. Students watch as 'Sal' adds the number 46 to 43. He references each number by its...
Khan Academy
U.S. National Debt (Scientific Notation Word Problem), Pre-Algebra
Sal uses a TI-85 graphing calculator to demonstrate how to check his work while he solves a complex word problem where he must use scientific notation to express his answer. This would be a handy video for an SAT prep or cumulative review.
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French Invasion of Russia, World History
The arrogance of Napoleon ultimately led to the failure of his final and most ambitious mission. Detailing one of the "top five famous military campaigns in all history," this video describes Napoleon's unsuccessful campaign to invade...
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How to Evaluate an Expression Using Substitution, Algebra I
Connect algebraic reasoning with temperature conversions. Sal expresses a conversion where he uses a formula to convert degrees Celsius to degrees Fahrenheit.
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A Look at a Seductive but Wrong Gibbs/Spontaneity Proof
Sal takes issue with a proof that some students suggested he use to calculate spontaneity in reactions. He contends that the proof is incorrect and uses this video to illustrate his reasons clearly.
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Shells, Subshells, and Orbitals
A more detailed description and definition of orbitals, and the role they play in the atomic world, are the focus of this video. The "P Orbitals" are described by taking a close look at the carbon element's properties. The periodic table...
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Introduction to Kinetics, Energy and Enzymes, Biology
The focus of this chemistry video is kinetics, which is the study of precisely what happens to compounds when they react together. Specifically, kinetics is the study of the rate of chemical reactions and the forces that affect that...
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Anatomy of a Muscle Cell
Previous videos have dealt with the proteins that produce mechanical motion and how nerves stimulate contraction. But this presentation explains, on a gross anatomical scale, how skeletal muscle is structured.
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Red Blood Cells, Human Anatomy and Physiology, Health and Medicine
By detailing the percentages of gases in the air we breathe, the lecturer instructs on respiration and the need for oxygen. He also recaps the structure of alveoli in our lungs and how they interact to allow gas exchange with our blood.
Khan Academy
How to Evaluate an Expression with Variables, Introduction to Algebra, Algebra I
Evaluate the expression 5t + 3. Use the provided variables to determine an answer. Scholars are provided with three different values for t and must evaluate the expression using each value for t. This resource would be appropriate for...
Khan Academy
Conversion Between Metric Units, Ratios, Proportions, Units, and Rates, Pre-Algebra
Math scholars with a basic grasp of units of measure will appreciate this video. Sal breaks down the process needed to convert between metric units. He defines kilo, hecto, and deka, then uses that framework to assist him in determining...
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The Distributive Law of Multiplication Over Subtraction, Pre-Algebra
This video is excellent preparation for order of operations and linear equations. There are two videos on the distributive property of multiplication. The first one showed why distribution works. This one shows the process clearly and...
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The Distributive Law of Multiplication Over Addition, Pre-Algebra
Elementary schoolers observe Sal evaluate the expression 4(8+3) and then use the distributive property to solve it. Using different colors to make the process transparent, Sal explains not only how to use the distributive property but,...
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Factoring Sum of Cubes, Polynomial and Rational Functions, Algebra II
Here is a special form of a sum of cubes problem, where students use algebraic multiplication to rewrite each term in expanded form. Sal gives an example before solving the problem to show the process that he will use to determine the...