Question

Resolva os sistemas aplicando a regra de Cramer: *​

Answer 1

Explicação passo-a-passo:

eu pesquisei aqui no brainly e foi tbm uma forma q eu consegui responder

Answer 2

Resposta:

$a)\\ \\ 2x-3y=-5\\ x+2y=8\\ \\ D=\left[\begin{array}{cc}+2&-3\\+1&+2\\\end{array}\right] =4-(-3)=4+3=7\\ \\\\ Dx=\left[\begin{array}{cc}-5&-3\\+8&+2\\\end{array}\right] =-10-(-24)=-10+24=14\\ \\ \\ Dy=\left[\begin{array}{cc}+2&-5\\+1&+8\\\end{array}\right] =16-(-5)=16+5=21$

$x=\frac{Dx}{D} =\frac{14}{7} =2\\ \\ y=\frac{Dy}{D} =\frac{21}{7} =3\\ \\ S\left \{ {{2,3} {}} \}$

$b)\\ \\ D=\left[\begin{array}{ccccc}+3&+2&+3&+3&+2\\+1&+1&+1&+1&+1\\-2&-3&+3&-2&-3\end{array}\right] =\\\\ \\ (9-4-9)-(-6-9+6)=-4-(-9)=-4+9=5\\ \\ D=5\\ \\\\ Dx=\left[\begin{array}{ccccc}+0&+2&+3&+0&+2\\+1&+1&+1&+1&+1\\-5&-3&+3&-5&-3\end{array}\right] =\\\\ \\ (0-10-9)-(-15+0+6)=-19-(-9)=-19+9=-10\\ \\ Dx=-10\\ \\ \\ Dy=\left[\begin{array}{ccccc}+3&+0&+3&+3&+0\\+1&+1&+1&+1&+1\\-2&-5&+3&-2&-5\end{array}\right] =\\\\ \\ (9+0-15)-(-6-15+0)=-6-(-21)=-6+21=15\\ \\ Dy=15$

$Dz=\left[\begin{array}{ccccc}+3&+2&+0&+3&+2\\+1&+1&+1&+1&+1\\-2&-3&-5&-2&-3\end{array}\right] =\\\\ \\ (0-4-15)-(0-9-10)=-19-(-19)=-19+19=0\\ \\ Dz=0$

$x=\frac{Dx}{D} =-\frac{10}{5} =-2\\ \\ y=\frac{Dy}{D} =\frac{15}{5} =3\\ \\ z=\frac{Dz}{D} =\frac{0}{5} =0\\ \\ \\ S=\left \{ {{-2,3,0} {}} \}$