Simultaneous equations like 𝒚 = 2𝒙 - 1 and 𝒚 = 𝒙 + 1 can be represented graphically. To solve the equations graphically, the two lines 𝒚 = 𝒙 + 1 and 𝒚 = 2𝒙 - 1 are drawn on the same diagram.

Attempting to solve the following system of equations using qr_solve(A, b) results in an error, although it appears the solution should exist: $$\mathbf{A} = \begin{bmatrix} 1 & -π/20 & (-π/20)^2 & ...