10)
a ) 8x+1=5x-5
8x-5x= -5 -1
3x = -6
x = (-6) :3
x= (-2) are solutie negativă
b) -4x+10=10-2x
-4x+2x=10-10
-2x=0
x=0:(-2)
x= 0
c) -3x+5=-9x+4
-3x+9x=4-5
6x=(-1)
x=(-1):6
x=-1,(6) are soluție negativă
d) 2(x+1) =6
2x+2 =6
2x=6-2
2x=4
x=4:2
x=2 are soluție pozitivă
e) 5(x-1)=2x+7
5x-5=2x+7
5x-2x=7+5
3x=12
x=12:3
x=4
f) 3(x+2)=2(x+4)
3x+6=2x+8
3x-2x=8-6
x=2
g) 6 = 4(x+1)-2(x+2)
6=4x+4-2x+4
-4x+2x=4+4-6
-2x=2
x=2:(-2)
x=(-1)
h) 4=5(x+1)-6
4=5x+5-6
4-5+6=5x
5x=5
x=5:5
x=1
i) 3(2x-5)=6(x-1)-9
6x-15=6x-6-9
6x-15=6x-15
6x-6x=-15+15
0=0
13)
a) 7x-7=6-3(x+1)
7x-7=6-3x+3
7x+3x=6+3+7
10x=16
x=16:10
x=1,6
b) 3x-4=x+2(x-2)
3x-4=x+2x-2
3x-4=3x-2
3x-3x=-2+4
0=2
c) x(x+1)=x^2+2x+1
×^2+x=x^2+2x+1
x^2+x-x^2-2x=1
x^2-x^2+x-2x=1
-x=1
x=1×(-1)
x=(-1)
d) 2(2x-5)=4(x-2)-6
4x-10=4x-8-6
4x-10=4x-14
4x-4x=-14+10
0=(-4)
e) 5(1-2x)+1=4(x+3)+8
5-10x+1=4x+12+8
6-10x=4x+20
-10x-4x=20-6
-14x=14
x=(-1)
f) -10{-2-2[(-4)^5:4^4-2]}=-2x
-10[-2-2(-4-2)]=-2x
-10[-2-2×(-6)]=-2x
-10(-2+12)=-2x
-10×10=-2x
-100=-2x
x=(-100):(-2)
x=50
