Răspuns:
b)2x+3y=5|-2x
x+3y=6
3y=5-2x
x+5-2x=6
3y=5-2x
-3x+5=6
-3x=1
x=1/3
3y=5-0.6
3y=4.4
y=4.4/3
d)
3x+y=-6
2x-2y=5
y=-6-3x
2x-2*-6-3x=5
y=-6-3x
2x-12-3x=5
y=-6-3x
5x-12=5
5x=17
x=17/5 aprox 3
y=-6+3*3.5
y=-6+10.5
y=-16.5
f)2x+5y=-11|*-4
3x+4y=10|*5
-8x-20y=44
15x+20y=50
8x=44
15x=50
23x=94
x=94/23
x=4
12+4y=10
4y=-2
y=-0.5