Question

a) observe as equações
x + y = 10
x - y = 3
x = 5y + 5
3y = x + 2
determine o valor de x e y

Answer 1

Corta os y

2x=13
2

X -5y=5 (.3)

-x 3y=2 (.5)

Corta os y

-2x=25 (.-1)

+2x=25
2

Answer 2

1) observe as equações

a)

(x + y = 10
(x - y = 3
----------------( + )
2x=13
x=13/2

13/2 + y = 10
y= 10 - 13/2
y= 7/2

R: ( 13/2 e 7/2 )




b)

(x = 5y + 5
(3y = x + 2
:
:
3y=5y+5+2
y= - 7/2
:
:
3. ( - 7/2 )= x + 2
x = - 25/2
:
:
:
:
( x , y )= ( - 25/2 e - 7/2 )