Question

Como Resolver?
x-y=3
4x+y=22

Answer 1

Resposta:

S={( 5 ; 2)}

Explicação passo-a-passo:

1x-1y=3

4x+y=22

Regra de Cramer:

(1 -1)

(4 1)

D= (1).(1)-(-1).(4)

D=1 +4

D= 5

( 3 -1)

(22 1)

DX= 1.(3)-(-1).(22)

DX= 3 +22

DX= 25

(1 3)

(4 22)

Dy= (1).(22)-(3).(4)

Dy= 22 -12

Dy= 10

X= DX/D = 25/5= 5

Y=Dy/D = 10/5= 2

Answer 2

S={5,2}

x-y=3

x=3+y

4(3+y)+y=22

12+4y+y=22

5y=22-12

5y=10

y=10/5

y=2

substitua.

3+y

3+2

x=5