Odpowiedź:
1. a) a + (-3) = a - 3
b) 2x - 4
c) b/3
2. 5+3*2-1 = 5+6-1 = 10
3. a) 7x+3y-2xy+1-3x-3xy+2 = 5x+3y-5xy+3
b) (x-2y)+(5x-7y) = x-2y+5x-7y= 6x-9y
c) (4x-7)-(10x+2) = 4x-7-10x-2 = -6x-9
4. a) -2x+4(x+1)=8
-2x+4x+4=8
2x=4 /: 2
x=2
b) 6(x+3)-x=4x
6x+18-x=4x
6x-x-4x= -18
x= -18
c)2x+9= -4(x-3)+5
2x+9= -4x+12+5
6x=17-9
6x=8 /:6
x=8/6
x=1 2/6 = 1 1/3
d)7x+8-5x+6=-6x+9-8x+7
2x+14= -14x+16
2x+14x = 16-14
16x=2 /: 16
x= 2/16 = 1/8
