\(v_A=20 \,m / s\)
\(v_B=30 \sqrt{2} \,m / s\) along \(45^{\circ}\) with \(x\)-axis
\(\vec{v}_B=v_B \cos 45^{\circ} \hat{i}+v_B \sin 45^{\circ} \hat{j}=30 \hat{i}+30 \hat{j}\)
\(\vec{v}_{B A}=\vec{v}_B-\vec{v}_A=30 \hat{i}+30 \hat{j}-20 \hat{i}\)
\(\vec{v}_{B A}=10 \hat{i}+30 \hat{j}\)