Question

Resolva os sistemas:

( x+y=50
(2x+y=150


(x+y=50
(3x+2y=120


(x+y=50
(2x+y=120

Answer 1

x+y=50 (-2)
2x+y=150

-2x-2y=-100
2x+y=150


-y=50
y=-50


x-50=50
x=100


S={100,-50}




2-

x+y=50 (-3)
3x+2y=120


-3x-3y=-150
3x+2y=120


-y=-30
y=30


x+30=50
x=20

S={20,30}



3-

x+y=50 (-2)
2x+y=120


-2x-2y=-100
2x+y=120


-y=20
y=-20

x-20=50
x=70

S={70,-20}