- (a) Use the Euclidean algorithm to show that the highest common factor of 168 and 66 is 6
(b) Use back substitution to determine integers \(a\) and \(b\) such that
$$168 a + 66 b = 6$$
(c) Explain why there are no integer solutions to the equation
$$168 x + 66 y = 10$$
(d) Solve the congruence equation
$$11 v \equiv 8 ( \bmod 28 )$$