## Algebra and Trigonometry 10th Edition

$x=-9, y=-4$
We divide the $R_1$ by $2$ and then subtract $3R_1$ from $R_2$: We have: $\begin{bmatrix} 1 & -2.5 & : 1 \\ 0 & 0.5 & : -2 \end{bmatrix}$ Divide $R_2$ by $0.5$. $\begin{bmatrix} 1 & -2.5 & : 1 \\ 0 & 1 & : -4 \end{bmatrix}$ Write the system of equations corresponding to the augmented matrix as follows: $x -2.5y=1 \\ y =-4$ and $x-2.5(-4)=1 \implies x=-9$ Therefore, $x=-9, y=-4$