1a
3x + 12 = 0 |4
x + 4 = 0
x=-4
1/4y - 1/2 = 0 /4
y-2 = 0
y = 2
2x+ 5y-10= 0\5
2/5x + y = 2
y=2 - 2/5 x
zad 2
a) x= -3, y= 5
(-3,5)
b
b)x=1/2 , y=-2x +4
y = -2 * 1/2 + 3 = 2
(1/2,2)
cc)y= -10 , 3x+2y-20= 0
3x-20-20=0
3x=40
x=13 1/3
(13 1/3, -10)
d) y= 2/3x -5 , -x+2y -1 = 0
-x + 4/3 x -10 - 1 = 0
1/3 x = 11
x = 33
y = 22 - 5 = 17
(33,17)
zad 3
2x-4y+2 = 0 , 2x+y-3= 0 i x+2y+1 = 0
2x-4y+2 = 0 , 2x+y-3= 0
x-2y=2
2x+y=3 / -2
x-2y=2
-4x-2y=-6
-3x=-4
x=4/3
2x+y-3= 0 i x+2y+1
x+2y=-1
-4x-2y=-6
x+2y=-1
-3x=-7
x--7/3
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