Question

Resolva pela regra de Cramer os sistemas
a) {3x+y=-1
{x-5y=21

Answer 1

{3x+y= -1

{x-5y=21

3 1

1 -5

dp=-15

ds=1

d=dp-ds=

d=-15-1=

d=-16

calculando Dx

-1   1

21   -5

=21    =5

Dx=5-21=-16

X=Dx\d

X=-16\-16

X=1

calculando Dy

3   -1

1    21

=-1   =63

Dy=63-(-1)=

Dy=63+1=64

Y=Dy\d

Y=64\-16=

Y=-4

solução(1,-4)