fxSolver

[T3sl4co1l]

This seems like it may be more handy than Wolfram Alpha, specifically for solving equations:
https://www.fxsolver.com/

I would suppose, usual free-cloud rules apply, don't submit anything you don't want others to read, etc.

Tim

[rstofer]

I'm using Symbolab.com for general equation solving and Desmos.com for graphing.  This in support of my grandson's college courses.

I also use  Matlab and wxMaxima for all of the more interesting work that I want to save and anything involving matrices.  Simultaneous equations are a piece of cake with wxMaxima.  Very handy for mesh and nodal analysis. 

Fortran shows up from time to time.  I spent some time coding Riemann Sums (integration of functions) and Euler's Method (for solving DEs).  Fortran produces an elegant solution to problems of sums and products.

I subscribe to Wolfram Alpha but I can't say I have used it very much.

Microsoft Mathematics is pretty good.

I don't use it but Maple comes up from time to time.

This is certainly an improvement over the days of slide rules.