To solve the simultaneous congruences $$2n + 6m\equiv 2 \pmod{10}$$ and $$n + m\equiv -2 \pmod{10}$$
I tried to add the two congruences together so I got: $$3n + 7m\equiv 0 \pmod{10}$$ But I am not sure if that's right and if it is, what to do next to calculate the two separate variables. If the question is like $n\equiv x \pmod y$ then it's simple enough to calculate