The curve $\displaystyle y=ax^2 + bx + c$ passes through the points $\displaystyle (x_1, y_1), (x_2, y_2), (x_3, y_3)$. Show that the coefficients a, b, and c are a solution of the system of linear equations whose augmented matrix is:

$\displaystyle \begin{bmatrix} x^2_1& x_1& 1& y_1 \\

x^2_2& x_2& 1& y_2 \\

x^2_3& x_3& 1& y_3 \end{bmatrix}

$

Just began linear algebra and having trouble understanding what this question is asking. I thought only constants/coefficients could go in the augmented matrix, but thex's andy's are variables. Confusing.