Solve this following

Show that the points $A, B$ and $C$ having position vectors $(\hat{i}+2 \hat{j}+7 \hat{k}),(2 \hat{i}+6 \hat{j}+3 \hat{k})$ and $(3 \hat{i}+10 \hat{j}-3 \hat{k})$ respectively, are collinear.