https://www.khanacademy.org/math/algebra-home/alg-rational-expr-eq-func/alg-direct-and-inverse-variation/v/direct-and-inverse-variation 2020-11-06T18:53:40Z Intro to direct & inverse variation Sal explains what it means for quantities to vary directly or inversely, and gives many examples of both types of variation. Sal Khan video https://cdn.kastatic.org/googleusercontent/z47mH-BxMUZ1Yrzgu3rebtng4EJg1z5mfzbk8HxVyAuvvxTMw6_CnzpkwbAsqAzPCwgTA2Y6QQ1Mc0bcMjehYOl70Q Intro to direct & inverse variation Sal explains what it means for quantities to vary directly or inversely, and gives many examples of both types of variation. https://cdn.kastatic.org/ka-youtube-converted/92U67CUy9Gc.mp4/92U67CUy9Gc.mp4 594 Variation https://www.khanacademy.org/math/algebra-home/alg-rational-expr-eq-func/alg-direct-and-inverse-variation/v/recognizing-direct-and-inverse-variation 2020-11-06T18:53:40Z Recognizing direct & inverse variation Sal gives many examples of two-variable equations where the variables vary directly, inversely, or neither. Sal Khan video https://cdn.kastatic.org/googleusercontent/vV0e0rb72IC_NH2QNpaNxGm96buKN8deIeu0-EvdR7KYV2EWHSuLSi-FWa0VZUbQZrd7JxaYEKM-ZaOxezxXUQUF Recognizing direct & inverse variation Sal gives many examples of two-variable equations where the variables vary directly, inversely, or neither. https://cdn.kastatic.org/ka-youtube-converted/3_DxJwDTbyQ.mp4/3_DxJwDTbyQ.mp4 425 Variation https://www.khanacademy.org/math/algebra-home/alg-rational-expr-eq-func/alg-direct-and-inverse-variation/e/direct_and_inverse_variation 2025-02-18T07:52:09.551150445Z Recognize direct & inverse variation Given a few two-variable equations, find those that show direct or inverse variation. Tomer Gal exercise https://www.khanacademy.org/math/algebra-home/alg-rational-expr-eq-func/alg-direct-and-inverse-variation/v/direct-variation-1 2021-06-28T22:10:45Z Direct variation word problem: filling gas Worked example: Model a context about filling gas with a direct variation equation. Sal Khan video https://cdn.kastatic.org/googleusercontent/8FEkx38fQ7Hy3kVkXrwzH2eG9q06krmVD-3UBrmqAi4oAVv920U9H9SbmCzioTDHOdawxsuQ0oOBp2weZLpsjT1e Direct variation word problem: filling gas Worked example: Model a context about filling gas with a direct variation equation. https://cdn.kastatic.org/ka-youtube-converted/rSadG6EtJmY.mp4/rSadG6EtJmY.mp4 219 Variation https://www.khanacademy.org/math/algebra-home/alg-rational-expr-eq-func/alg-direct-and-inverse-variation/v/inverse-variation-application 2020-11-06T18:53:41Z Inverse variation word problem: string vibration Sal models a context about lengths of strings and the frequency of their vibrations! with an inverse variation equation. Sal Khan video https://cdn.kastatic.org/googleusercontent/R_4NTByLfhg149OVI4HOdNoXR7KJf9RU6sHOxD2WH8dA_5uOyqOL0jIRSZiOPl7I4ulKELzfPj8My3G6RjwcSFHY3g Inverse variation word problem: string vibration Sal models a context about lengths of strings and the frequency of their vibrations! with an inverse variation equation. https://cdn.kastatic.org/ka-youtube-converted/lkP-E2LUnjA.mp4/lkP-E2LUnjA.mp4 282 Variation https://www.khanacademy.org/math/algebra-home/alg-rational-expr-eq-func/alg-direct-and-inverse-variation/v/direct-inverse-and-joint-variation 2020-11-06T18:53:41Z Recognizing direct & inverse variation: table Sal is given a table with a few values of the variables x and y, and determines whether the variables vary directly or inversely. Sal Khan video https://cdn.kastatic.org/googleusercontent/0aWjMFwDAgJwwEiyh3iTClZNrx4JQu3gdzDbWHIPy97uX8Eh3ZSGkhjJLg6QfR5zObGDbMCGdL23r1exBdTbpWE Recognizing direct & inverse variation: table Sal is given a table with a few values of the variables x and y, and determines whether the variables vary directly or inversely. https://cdn.kastatic.org/ka-youtube-converted/v-k5L0BPOmc.mp4/v-k5L0BPOmc.mp4 330 Variation https://www.khanacademy.org/math/class-8-bridge-course-mh/x32413ee700b4a348:direct-and-inverse-variation/x32413ee700b4a348:direct-and-inverse-proportion/e/direct-proportions 2026-04-01T15:58:47.49881528Z Direct proportions Given two values for quantities and that they're directly proportional, find a quantity that corresponds to a third value. Nick Kokkinis exercise https://www.khanacademy.org/math/class-8-bridge-course-mh/x32413ee700b4a348:direct-and-inverse-variation/x32413ee700b4a348:direct-and-inverse-proportion/e/commercial-math-7-b 2026-02-20T04:30:45.963786187Z Inverse proportion Commercial math ashish exercise https://www.khanacademy.org/math/9th-grade-philippines/x22ecd091eddebb21:2nd-quarter/x22ecd091eddebb21:word-problems-involving-variations/e/word-problems-on-direct-and-inverse-proportion 2025-07-16T06:17:27.519405562Z Word problems on direct and inverse proportion Let's solve some word problems on direct and inverse proportion. ashish exercise https://www.khanacademy.org/math/class-8-od/x97648b3e69d960e3:variation-odia-class-8/x97648b3e69d960e3:direct-and-inverse-variation-odia-class-8/v/joint-variation 2025-07-16T05:34:14.162196692Z Joint Variation What happens when a quantity depends on two variables at once — like both length and breadth? This video introduces joint variation in a simple, visual way. You'll see how area changes with length and breadth, understand how joint variation works, and learn to derive its formula step by step. We wrap it up with a solved example that brings everything together and helps you grasp the concept with confidence. Khan Academy video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Joint Variation What happens when a quantity depends on two variables at once — like both length and breadth? This video introduces joint variation in a simple, visual way. You'll see how area changes with length and breadth, understand how joint variation works, and learn to derive its formula step by step. We wrap it up with a solved example that brings everything together and helps you grasp the concept with confidence. https://cdn.kastatic.org/ka-youtube-converted/sHuy-Kc6Gms.mp4/sHuy-Kc6Gms.mp4 671 Variation