Question

transforme os sistemas lineares em determinantes e resolva a 2 x - 3y = - 5, x +2y=8​

Answer 1

Resposta:

Explicação passo-a-passo:

2x-3y= -5

x+2y=8

Transformando o sistema linear em determinantes:

$\left[\begin{array}{ccc}2&-3\\1&2\end{array}\right] .\left[\begin{array}{ccc}x\\y\end{array}\right] =\left[\begin{array}{ccc}-5\\8\end{array}\right]$

Regra de Kramer

$\displaystyle \Delta=\left[\begin{array}{ccc}2&-3\\1&2\end{array}\right]=4-(-3)=4+3=7\\\\\Delta x=\left[\begin{array}{ccc}-5&-3\\8&2\end{array}\right]=-10-(-3).8=-10+24=14\\\\\Delta y=\left[\begin{array}{ccc}2&-5\\1&8\end{array}\right]=16-(-5).1=16+5=21\\\\\\x=\frac{\Delta x}{\Delta} =\frac{14}{7} =2\\\\\\y=\frac{\Delta y}{\Delta} =\frac{21}{7} =3$