Resposta :
Resposta:
Explicação passo-a-passo:
[tex]\left[\begin{array}{ccc}2&x\\3&9\\\end{array}\right]=\left[\begin{array}{ccc}1&-1&0\\2&3&x\\-1&2&1\end{array}\right][/tex]
vamos resolver:
[tex]2.9-3x=3+x+0-0-2x+2[/tex]
[tex]18-3x=5-x[/tex]
[tex]13=2x[/tex]
[tex]x=\frac{13}{2}[/tex]