21.4 The Method of Undetermined Coefficients: Working Back from Points
Point 3 of 5
21.4.3 Two Points Pin Down a Linear Function
Core idea
A linear function has two unknowns, k and b, so plug in two points, set up the pair of equations, and solve for y=kx+b.
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 · 21.4.3 Two Points Pin Down a Linear Function