Polar ↔ Rectangular Coordinate Converter (Free)
Free polar and rectangular coordinate converter: switch a point between (x, y) and (r, θ) in degrees or radians, with the formulas and a diagram.
Linear Equation Solver — Solve for x Step by Step (Free)
Free linear equation solver: solve ax + b = cx + d for x with full step-by-step working, and a check that substitutes the answer back in.
