# Number theory resources

### Test Yourself (1)

Greatest common divisor and congruences - Numbas

Given two numbers, find the greatest common divisor (gcd), then use Bezout's algorithm to find 's' and 't' such that 'as+bt=operatorname{gcd}(a,b)'.
Finally, find all solutions of an equation $mod b$. Numbas resources have been made available under a Creative Commons licence by Bill Foster and Christian Perfect, School of Mathematics & Statistics at Newcastle University.