Szczegółowe wyjaśnienie:
a)
3x+y=-2
2x-y =-3
3x+y +2x -y = -2 -3
5x = -5
x = -1
3x+y=-2
3 * -1 +y = -2
-3 + y = -2
y = 1
b)
x - 4y = -2
2x +y = 5
x-4y = -2
8x + 4y = 20
x - 4y +8x + 4y = -2 +20
9x = 18
x = 2
2 * 2 + y =5
4+ y = 5
y = 1
c)
1/2x + 1/3y = 1
-2x +y =-4
2x +4/3y = 4
-2x +y = -4
2x +4/3y -2x +y = 4-4
2 1/3y = 0
y = 0
-2x +0 = -4
-2x = -4
x = 2