How do we solve quadratic congruences such as $X^2+ 3X \equiv -5 \mod{7}$?
98387
How to solve polynomial equations in a field and/or in a ring?
96237
$1^2 + 2^2 + 3^2 + \cdots + (n-1)^2 \equiv 0$ mod n iff $n \equiv \pm 1$ mod 6
2904
Solving linear congruence (modular inverse or fraction) via gcd Bezout equation
56803
Finding solutions to congruence equations
112390
Solutions of $x^2 \equiv 1 \pmod N$
42754
Modular arithmetic: division, fractions, solving linear congruences
131395
Solving linear congruence $2x + 11 \equiv 7 \pmod 3$
70392
System of congruences with variable
103499
$x^2 \equiv a \mod p$, $\ x^2 \equiv b \mod p$, and $x^2 \equiv ab \mod p$, prove either all three are solvable or exactly one
30045
Solving linear congruences by hand: modular fractions and inverses
119068
How to solve inhomogeneous quadratic forms in integers?
68252
Chinese Remainder Theorem solvability for non-coprime moduli
21530
How many solutions of $\mod 63$ : $x^2=1 \pmod7 $ and $x^3=1\pmod 9$
94965
Solve $x\equiv 1\pmod2$, $x\equiv 2\pmod3$, $x\equiv 3\pmod4$, $x\equiv 4\pmod5$, $x\equiv 5\pmod6$ and $x\equiv 0\pmod7$
155743
Why does the equation $x^2\equiv2 \pmod 5$ have no solutions?
8784
modulo version of the quadratic formula and Euler's criterion
92700
How can I solve $x^2 \equiv 19 \pmod {59}$.