zad.8
a)
3x+7=-5/-7
3x=-12/:3
x=-4
b)
-8x+4=-5x+16/-(-5)
-8x+5x+4=16/-4
-3x=12/:(-3)
x=-4
c)
2(x+6)=-4
2x+12=-4/-12
2x=-16/:2
x=-8
d)
5-x=2x+9/-2x
5-x-2x=9/-5
-3x=4/:(-3)
x=-1 i 1/3
zad.9
a)
2a-3=a+1/-a
2a-a-3=1/+3
a=4
b)
4b+3=3b-4/-3b
4b-3b+3=-4/-3
b=-7
c)
7+3c=5+2c/-2c
7+3c-2c=5/-7
c=-2
d)
5d+2=3d/-2
5d=3d-2/-3d
5d-3d=-2
2d=-2/:2
d=-1
e)
6e-7=9e+5/-9e
6e-9e-7=5/+7
-3e=12/:(-3)
e=-4
f)
6f-1=f+2/-f
6f-f-1=2/+1
5f=3/:5
f=3/5