While I do find it ridiculous that nobody gets them, it is ridiculous to teach students quadratic equations at ANY non-optional year. After the 9th year, you can drop out of school, or choose an educational path (Mathematics-related subjects, or Language-related subjects). I asked my History teacher if she has ever solved a quadratic equation after leaving the university, and guess what, the answer was no. It is ridiculous to teach every student quadratic equations, when many of them are never going to use that knowledge in their life again. Same goes for Ancient Greek, Computers, Biology and Art.