21.4 The Method of Undetermined Coefficients: Working Back from Points
Point 2 of 5
21.4.2 One Point Pins Down a Direct Proportion
Core idea
A direct proportion is missing only k, so plugging in a single known point is enough to solve for y=kx.
Module goal. Master the general technique for recovering y=kx+b from given conditions, opening the reverse route from "graph or data" back to "formula."
eastmath.com · 21.4 The Method of Undetermined Coefficients: Working Back from Points · 21.4.2 One Point Pins Down a Direct Proportion