Answer
Using the property that
$$A \operatorname{adj}(A)=\det(A) I_n$$
together with the fact that $\det(A)=0$, then $A \operatorname{adj}(A)$ must be the zero matrix.
Work Step by Step
Using the property that
$$A \operatorname{adj}(A)=\det(A) I_n$$
together with the fact that $\det(A)=0$, then $A \operatorname{adj}(A)$ must be the zero matrix.
