Parabola - quadratic and biquadratic equation solver, real and complex solutions

Solver for quadratic equations (ax^2+bx+c=0) and biquadratic equations (ax^4+bx^2+c=0).
The app can calculate real and complex solutions.
It is also possible to plot the functions and to zoom in and out.
You can input decimal coefficients (e.g a = 1.5) or fractions (e.g a = -4/3).
This solver is useful for mathematics, physics and algebra calculus.