As someone who is quite good at math and mid-level algebra as it's presented... I honestly don't see how a bot could solve your equations. You have a bot that can read an equation, decide the function of the 1st variable, then use a drop down menu and pick the correct multiplier?

I can solve some of the equations in a matter of seconds. It's certainly not possible to input the variables and have some program spit out the right result in the time that my mind can work.

There were times that I was a split second too slow and just missed out on the solution, but I have no illusion that there was anything other than another human on the receiving end of the block.

I like that there will be other ways of brainmining, on the future, but I think you have it right regarding  Mathematical based equations. Mathematics is the universal language.

What you are suggesting with pictures and captchas is putting your puzzles into only a few languages. Personally I speak English and I'm good at doing math in my head, so I like the direction wherever it goes. You either get a team of interpreters or include math in order to get universal adoption.

Great project BTW. This is like a video game, trying to get the most coins, using your brain.

You took 5 billion and I get that, but it's not the greatest business model.

If you were to start spreading that around and putting DIRA on the crypto map, You have a hell of an idea.