Question

x+y=4
2x+y=4 me ajude !

Answer 1

x+y=4 
x=4-y

2(4-y)+y=4
8-2y+y=4
-2y+y=4-8
-y=-4(-1)
y=4

x=4-y
x=4-4
x=0

Answer 2

{x+y=4
{2x+y=4
x=4-y
2(4-y)+y=4
8-2y+y=4
-2y+y=4-8
-y=-4
y=4
x=4-4
x=0
espero ajudar ♥