Question

Considere o sistema: 2x–2y=6 e x+y=4y. A soma dos valores de x e y é:
( A ) 6
( B ) 3
( C ) 9/2
( D ) 3/2

Answer 1

Resposta:

2x–2y=6

x+y=4y, x=3y

6y-2y=6

4y=6

y=6/4= 3/2

x= 3.3/2= 9/2

x+y= 12/2= 6

Answer 2

Explicação passo-a-passo:

{2x–2y=6

{x+y=4y

{2x-2y=6

{x=4y-y

{2x-2y=6

x=3y

2x-2y=6

2*3y-2y=6

6y-2y=6

4y=6

y=6/4(÷2)

y=3/2

x=3y

x=3*3/2

x=9/2

Soma de x e y

3/2+9/2

3+9/2

12/2

6

Opção A