Need to use something besides reCaptcha

[Lasa]

Because the recaptcha only works on principle domain address any domain name pointing at it make the recaptcha not work and show an error.
I would like to try a simple 2+2 = 3 formula, were a person would need to input 3 to submit the form.
How would I make this happen?

Lasa

[Pablo]

Do you mean this?

[Lasa]

Actually, I was thinking of reinventing the wheel, but you made it supper easy for me thanks!
Lasa