Sal picks the graph that matches f(x)=(ax^m+bx+12)/(cx^m+dx+12) based on its y-intercept. Watch the next lesson: https://www.khanacademy.org/math/math-1-2-3/math3/math3-rational-exp-eq-func/math3-rational-func-graphs/v/graphs-of-rational-functions-horizontal-asymptote?utm_source=YT&utm_medium=Desc&utm_campaign=highschoolmath Missed the previous lesson? https://www.khanacademy.org/math/math-1-2-3/math3/math3-rational-exp-eq-func/math3-rational-func-graphs/v/finding-asymptotes-example?utm_source=YT&utm_medium=Desc&utm_campaign=highschoolmath High School Math on Khan Academy: Did you realize that the word "algebra" comes from Arabic (just like "algorithm" and "al jazeera" and "Aladdin")? And what is so great about algebra anyway? This tutorial doesn't explore algebra so much as it introduces the history and ideas that underpin it. About Khan Academy: Khan Academy is a nonprofit with a mission to provide a free, world-class education for anyone, anywhere. We believe learners of all ages should have unlimited access to free educational content they can master at their own pace. We use intelligent software, deep data analytics and intuitive user interfaces to help students and teachers around the world. Our resources cover preschool through early college education, including math, biology, chemistry, physics, economics, finance, history, grammar and more. We offer free personalized SAT test prep in partnership with the test developer, the College Board. Khan Academy has been translated into dozens of languages, and 100 million people use our platform worldwide every year. For more information, visit www.khanacademy.org, join us on Facebook or follow us on Twitter at @khanacademy. And remember, you can learn anything. ... https://www.youtube.com/watch?v=YElHmwdbkzQ Note: All Khan Academy content is available for free at (www.khanacademy.org)

When doing algebra, we sometimes make mistakes! It's important to be able to check our own work (and other people's work) for correctness. Practice this lesson yourself on KhanAcademy.org right now: https://www.khanacademy.org/math/cc-seventh-grade-math/cc-7th-variables-expressions/cc-8th-two-step-equations-dec-frac/e/find-the-mistake-two-step-equations?utm_source=YT&utm_medium=Desc&utm_campaign=7thgrade Watch the next lesson: https://www.khanacademy.org/math/cc-seventh-grade-math/cc-7th-variables-expressions/cc-7th-linear-eq-word-probs/v/basic-linear-equation-word-problem?utm_source=YT&utm_medium=Desc&utm_campaign=7thgrade Missed the previous lesson? https://www.khanacademy.org/math/cc-seventh-grade-math/cc-7th-variables-expressions/cc-8th-two-step-equations-dec-frac/v/two-step-equations?utm_source=YT&utm_medium=Desc&utm_campaign=7thgrade Grade 7th on Khan Academy: 7th grade takes much of what you learned in 6th grade to an entirely new level. In particular, you'll now learn to do everything with negative numbers (we're talking everything--adding, subtracting, multiplying, dividing, fractions, decimals... everything!). You'll also take your algebraic skills to new heights by tackling two-step equations. 7th grade is also when you start thinking about probability (which is super important for realizing that casinos and lotteries are really just ways of taking money away from people who don't know probability) and dig deeper into the world of data and statistics. Onward! (Content was selected for this grade level based on a typical curriculum in the United States.) ... https://www.youtube.com/watch?v=6q8mk7z72AU Note: All Khan Academy content is available for free at (www.khanacademy.org)