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 Direct and indirect variation https://www.khanacademy.org/math/algebra-home/alg-rational-expr-eq-func/alg-direct-and-inverse-variation/v/proportionality-constant-for-direct-variation 2020-06-23T07:22:42Z Proportionality constant for direct variation Worked example: y is directly proportional to x, and y=30 when x=6. Find the value of x when y=45. Sal Khan video https://cdn.kastatic.org/googleusercontent/TqecRdK2rrGW3R3-2cGPTlwe2RP-ZMRJBqyNsTaCMhwdLXBJBqHrf6V5ISx7GcY99RyGolcC8Smx1_iEFCpGiWOz Proportionality constant for direct variation Worked example: y is directly proportional to x, and y=30 when x=6. Find the value of x when y=45. https://cdn.kastatic.org/ka-youtube-converted/c6-FJRda_Vc.mp4/c6-FJRda_Vc.mp4 104 Direct and indirect variation https://www.khanacademy.org/math/cc-seventh-grade-math/cc-7th-ratio-proportion/cc-7th-equations-of-proportional-relationships/v/equations-of-proportional-relationships 2021-06-30T17:51:05Z Equations for proportional relationships Learn how to write a proportional equation y=kx where k is the so-called "constant of proportionality". video https://cdn.kastatic.org/googleusercontent/FfP3iGtv8JFYOzzPHKAW1AnFGE22X5Cg95DUijI99X6lvUprTl2PlQ6hpD7XDR5FNbqsiS0SlTcFamRplhhNelS- Equations for proportional relationships Learn how to write a proportional equation y=kx where k is the so-called "constant of proportionality". https://cdn.kastatic.org/ka-youtube-converted/qcz1Cm_-l50.mp4/qcz1Cm_-l50.mp4 301 Direct and indirect variation https://www.khanacademy.org/math/cc-seventh-grade-math/cc-7th-ratio-proportion/7th-constant-of-proportionality/v/example-identifying-a-proportional-relatioship-given-a-constant-of-proportionality 2022-10-06T11:16:59.256015857Z Constant of proportionality from tables Identifying proportionality constants by looking at tables of values. video https://cdn.kastatic.org/googleusercontent/gHcfjy1AtDHtp2HNzU9eShRhLitaKNoxZetLuW255pnFiuYJL6x-6O9-m3eAhC-RRfu5pSIHaKi5tG6zudy4bq8 Constant of proportionality from tables Identifying proportionality constants by looking at tables of values. https://cdn.kastatic.org/ka-youtube-converted/rzDQ_ZIpi84.mp4/rzDQ_ZIpi84.mp4 154 Direct and indirect variation https://www.khanacademy.org/math/cc-seventh-grade-math/cc-7th-ratio-proportion/7th-constant-of-proportionality/e/constant-of-proportionality-from-tables 2026-03-05T16:00:37.302781114Z Constant of proportionality from tables (with equations) Use the equation, y=rx to identify r from a table of values. Lindsay exercise https://www.khanacademy.org/math/cc-seventh-grade-math/cc-7th-ratio-proportion/7th-constant-of-proportionality/v/proportionality-constant-from-table 2021-06-30T17:51:06Z Constant of proportionality from table (with equations) Sal identifies the constant of proportionality from table. video https://cdn.kastatic.org/googleusercontent/63GNoFU80M-0tSmCFrrDgWBD6xo5AkTESgwiCMvsW8jPSL2XBlx7Tbv4Q5lA2xcInrvZ1uvJQhQqxNBcxwsSqZw Constant of proportionality from table (with equations) Sal identifies the constant of proportionality from table. https://cdn.kastatic.org/ka-youtube-converted/5Ilo0pw3iL8.mp4/5Ilo0pw3iL8.mp4 105 Direct and indirect 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 Direct and indirect 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-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 Direct and indirect variation 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 Direct and indirect variation https://www.khanacademy.org/math/algebra-home/alg-rational-expr-eq-func/alg-direct-and-inverse-variation/v/direct-variation-application 2021-06-28T22:10:43Z Direct variation word problem: space travel Sal models a context about space travel with a direct variation equation. Sal Khan video https://cdn.kastatic.org/googleusercontent/T4dzWSxhWVAP2YjPK3MKdv6sIoAEbEe6-E7W4d90X9rSTh_rcWAYVWwdpNCV6N1TC_sbC2fY1npwhLnvHUwzTYvM Direct variation word problem: space travel Sal models a context about space travel with a direct variation equation. https://cdn.kastatic.org/ka-youtube-converted/ZsjfUUJUq9s.mp4/ZsjfUUJUq9s.mp4 122 Direct and indirect variation https://www.khanacademy.org/math/9th-grade-math-revised-k-to-10-3-terms/x1e64c39423990571:3rd-quarter/x1e64c39423990571:direct-and-indirect-variation/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