Roots · systems · curve fitting
🟰 Equation Solver
Quadratics, cubics, linear systems & regression — with a plot
x² +x += 0
x³ +x² +x += 0
Quadratics/cubics show real & complex roots (cubic via Cardano/trig). Linear systems use Gaussian elimination and report a unique, no, or infinite solution. Regression is least-squares polynomial with R². The plot marks roots / the fitted curve.