Răspuns:
1.a)
x= 4-y
2(4-y)+y= 7
8- 2y+y=7
-y= -1
y=1
x = 4-y= 4-1= 3
Explicație pas cu pas:
b)x-y=0
x=y
2x+ 3x= 10
5x= 10
x= 2
y=2
Ex.2
a) x= 4-y
2( 4-y)-y= -1
8-2y-y= -1
-3y= -9
y= 3
x= 4-y= 4-3=1
