# statistics – Distribution of X

$$X_1+X_2$$ and $$X_1-X_2$$ are $$i.i.d$$. $$N(1,4)$$ What is the distribution of $$X = (X_1,X_2)^T$$?
I know $$i.i.d.$$ is an independent and identically distributed random variable but I don’t know how to use it to solve this problem that contains a column vector.