Respuesta :
Answer:
[tex]\left[\begin{array}{ccc}3&-1&\\-1&1/2\\\end{array}\right][/tex]
Step-by-step explanation:
The matrix system for the linear equations: x + 2y = 8, 2x + 6y = 9
[tex]\left[\begin{array}{ccc}1&2&\\2&6\\\end{array}\right] \left[\begin{array}{ccc}x\\y\end{array}\right] = \left[\begin{array}{ccc}8\\9\end{array}\right][/tex]
To get the coefficient of x and y, the inverse of the first matrix (let the first matrix be A) must be known.
[tex]A^{-1}[/tex] = (1 / determinant of A) x Adjoint of A
the determinant of A = (1 x 6) - (2 x 2) = 6 - 4 = 2
Adjoint of A = [tex]\left[\begin{array}{ccc}6&-2&\\-2&1\\\end{array}\right][/tex]
[tex]A^{-1}[/tex]= [tex]\frac{1}{2} \left[\begin{array}{ccc}6&-2\\-2&1\end{array}\right][/tex] = [tex]\left[\begin{array}{ccc}3&-1&\\-1&1/2\\\end{array}\right][/tex]
