Question

Solve using determinant
2x-1=1
3x+2y=12
and prove by graph

Answer 1

Hello,


`$ \left \{ {{2x-y=1} \atop {3x+2y=12}} \right. $`


`\Delta= \left[\begin{array}{cc}2&-1\\3&2\end{array}\right] =4+3=7\\ \Delta_1= \left[\begin{array}{cc}1&-1\\12&2\end{array}\right] =2+12=14\\ \Delta_2= \left[\begin{array}{cc}2&1\\3&12\end{array}\right] =24-3=21\\\\ \left \{x= (\Delta_1)/(\Delta) = (14)/(7) =2} \atop { y= (\Delta_2)/(\Delta) = (21)/(7) =3} \right`