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This page provides a list of educational videos related to Proportion Problems and Algebra. You can also use this page to find sample questions, apps, worksheets, lessons , infographics and presentations related to Proportion Problems and Algebra.
Mountain height word problem
By Khan Academy
Using some basic algebra to solve what looks like a hairy word problem that involves proportions.
Recognizing rational and irrational expressions
By Khan Academy
Sal shows how to determine whether the following expressions are rational or irrational: 9 + ������������������(45), ������������������(45)/ (3*������������������(5)), and 3*������������������(9).
DEPRECATED Simplifying rational expressions 4
By Khan Academy
Sal solves the following problem:������������Given a rectangle with length a^2+6a+27 and width a^2-9, write the ratio of the width to the length as a simplified rational expression.
DEPRECATED Simplifying rational expressions 4
By Khan Academy
Sal������������simplifies and states the domain of (2x^2+13x+20)/(2x^2+17x+30).
Speed translation | Ratios, proportions, units, and rates | Pre-Algebra | Khan Academy
By Khan Academy
This video takes us through some more advanced unit conversion problems. Here, we can see how to make multiple conversions in the same problem concerning speed. Take particular note of how the units change in each step. More importantly, note how, step by step, our units slowly change into the units we want for our final answer. If you are having trouble understanding why this happens, go to the key concept described at 2:20 in the video. Note that this only occurs when multiplying two quantities, not when adding them!
Finding average speed or rate | Ratios, proportions, units, and rates | Pre-Algebra | Khan Academy
By Khan Academy
Using the formula for finding distance we can determine Usian Bolt's average speed, or rate, when he broke the world record in 2009 in the 100m. Watch.
Example Problem - Adding and Subtracting Rational Expressions (Multi-Step)
By Khan Academy
Khan Academy presents Adding and Subtracting Rational Expressions, an educational video resource on math.
Simplify rational expressions using advanced factorization methods
By Khan Academy
Sal������������simplifies and states the domain of (2x^2+13x+20)/(2x^2+17x+30).
Solve equations with two rational expressions
By Khan Academy
Sal solves the following equation and eliminates the resulting extraneous solution: (x^2)/(x+2)=4/(x+2).
Simplify rational expressions using advanced factorization methods
By Khan Academy
Sal������������simplifies and states the domain of (2x^2+13x+20)/(2x^2+17x+30).
Solve equations with two rational expressions
By Khan Academy
Sal solves the equation 5/(2x)-4/(3x)=7/18 by first finding the LCM (least common multiple) of 2x and 3x.
Simplify rational expressions by canceling monomial factors
By Khan Academy
Sal simplifies (28b^6)/(7b) as 4b^5.
Simplify rational expressions by canceling monomial factors
By Khan Academy
Sal simplifies (28b^6)/(7b) as 4b^5.
Simplify rational expressions by canceling binomial factors
By Khan Academy
Sal solves the following problem:������������Given a rectangle with length a^2+6a+27 and width a^2-9, write the ratio of the width to the length as a simplified rational expression.
Simplify rational expressions by canceling binomial factors
By Khan Academy
Sal������������simplifies and states the domain of (x^2-36)/(6-x).
Simplify rational expressions by canceling monomial factors
By Khan Academy
Sal explains what it means to simplify a rational expression and why we would want to do that. Just don't forget the excluded values!
Solve equations with two rational expressions
By Khan Academy
Sal solves the equation 4/(p-1)=5/(p+3).
Example Problem - Adding and Subtracting Rational Expressions (Multi-Step)
By Khan Academy
Khan Academy presents Adding and Subtracting Rational Expressions, an educational video resource on math.
Operate on rational expressions
By MathPlanetVideos
Simplify the given expression (x/6−6/x)/(x+6)(x−6)6x
DEPRECATED Simplifying rational expressions 4
By Khan Academy
Sal������������simplifies and states the domain of (x^2-36)/(6-x).