Have you tried the Wolfram Alpha app? I didn't try all of the examples you posted, but graphing a circle works fine. I use this app all the time to help me sim

Have you tried the Wolfram Alpha app? I didn't try all of the examples you posted, but graphing a circle works fine. I use this app all the time to help me simplify expressions (I'm an engineer - I use math, I love math, but I am no mathematician, so I seek shortcuts where I can to save time). 1.) Compute '10 = x^2 + y^2' with the Wolfram|Alpha website (https://www.wolframalpha.com/input/?i=10+%3D+x%5E2+%2B+y%5E2 https://www.wolframalpha.com/input/?i=10+%3D+x%5E2+%2B+y%5E2) or mobile app (wolframalpha:///?i=10+%3D+x%5E2+%2B+y%5E2).