Question

a) X+Y=7
2X-Y=-1



b) X+2Y=5
2X+Y=-2​

Answer 1

Explicação passo-a-passo:

a)

( X+Y=7

( 2X-Y=-1

========(+)

3x=6

x=6/3

x=2

x+y=7

2+y=7

y=7-2

y=5

S ( 2 e 5 )

b)

(X+2Y=5

(2X+Y=-2 × (-2)

(X+2Y=5

(-4x-2y=4

========(+)

-3y= 9. × ( - 1)

3y= - 9

y= - 9/3

y= - 3

x + 2y = 5

x + 2.(-3) = 5

x - 6 = 5

x = 5 + 6

x = 11

S ( 11 e - 3 )