To find a, b, c. It is assumed that the element a₃₁ (which is currently 9) should be a.

Step 1: Solve Question 1(a).
For matrix $A$ to be symmetric, its transpose $A^T$ must be equal to $A$. This means $a_{ij} = a_{ji}$ for all $i, j$.
The given matrix is $A = \begin{pmatrix} 9 & -6 & 2 \\ b & c & -2 \\ 9 & -2 & 4 \end{pmatrix}$.
The question asks to find $a, b, c$. It is assumed that the element $a_{31}$ (which is currently 9) should be $a$.
So, let $A = \begin{pmatrix} 9 & -6 & 2 \ b & c & -2 \ a