Q.A = (a; 6) and B = (3; b) [2×1 column matrices] and A = B, then (a, b) is equal to: OR If a + b + c = 0, then value of |a b c; b c a; c a b| (3×3 determinant) is:

Two matrices are equal only when every corresponding entry matches; compare entries one at a time.

Step 1. $\begin{bmatrix}5 & 3\\ x & 7\end{bmatrix} = \begin{bmatrix}y & 3\\ 7 & x\end{bmatrix}$.

Step 2. Comparing the $(1,1)$ entries: $5=y \Rightarrow y=5$.

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Two matrices are equal iff every corresponding entry is equal — match the entries of $A$ and $B$ directly.

Given $A=\begin{pmatrix}a\\6\end{pmatrix}$ and $B=\begin{pmatrix}3\\b\end{pmatrix}$, with $A=B$.

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