Respuesta:
1)
[tex]\begin{bmatrix}3x+y=16\\ 5x-y=24\end{bmatrix}\\\\\\\begin{bmatrix}5\cdot \frac{16-y}{3}-y=24\end{bmatrix}\\\\\\\begin{bmatrix}\frac{80-8y}{3}=24\end{bmatrix}\\\\\\x=\frac{16-1}{3}\\\\\\x=5\\\\\\x=5,\:y=1[/tex]
2)
[tex]\begin{bmatrix}x+y=4\\ x+2y=6\end{bmatrix}\\\\\\\begin{bmatrix}4-y+2y=6\end{bmatrix}\\\\\\\begin{bmatrix}4+y=6\end{bmatrix}\\\\\\x=4-2\\\\\\x=2\\\\\\x=2,\:y=2[/tex]
3)
[tex]\begin{bmatrix}x-y=4\\ x+3y=0\end{bmatrix}\\\\\\\begin{bmatrix}4+y+3y=0\end{bmatrix}\\\\\\\begin{bmatrix}4+4y=0\end{bmatrix}\\\\\\x=4-1\\\\\\x=3\\\\\\x=3,\:y=-1[/tex]
