If $4x\equiv 8\pmod{20}$ and $3x\equiv 16\pmod{20}$, then what is the remainder when $x^2$ is divided by $20$?
tysm!
Using "CRT + MMI", we have:
(4 x) mod 20 = 8 (3 x) mod 20 = 16, solve for x
x = 20m + 12, where m = 0, 1, 2, 3.........etc.
x =20 * 1 + 12 = 32
x^2 =32^2 mod 20 == 4 - The remainder.
