👉 In number theory, a congruence is a statement that two expressions or numbers are equal. It involves either an equation or an inequality. For example: 1) 2x + 3 = 5 2) x^2 - 4 = 0 These are both congruences because they have exactly one solution for any given value of x, which is the number 2. In mathematics, a congruence is usually denoted by an equation or inequality symbol.
