a) Calculam: 3[2-4(x-1)]=3(2-4x+4)=3(6-4x)=18-12x
Calculam: 2[3-2(x+1)]=2(3-2x-2)=2(1-2x)=2-4x
Facem scaderea => 18-12x-(2-4x)=18-12x-2+4x
16-8x=8x => 16=16x => x=1, x∈Ν
b) Calculam: -2[5-3(x+1)]=-2(5-3x-3)=-2(2-3x)=6x-4
Calculam: 4[7-2(x-1)]=4(7-2x+2)=4(9-2x)=36-8x
Rezolvam ecuatia:
6x-4=36-8x-34=>6x-4=2-8x=>14x=6= x=6/14=3/7, x∉Ν (x nu are solutii in N)
c) Calculam: 3[(x+1)*2-6]=3(2x+2-6)=3(2x-4)=6x-12
Calculam: 4[(x-2)*(-2)-7]=4(4-2x-7)=4(-2x-3)=-8x-12
Rezolvam ecuatia:
6x-12=-8x-12=> 6x=-8x => x=0, x∉Ζ* (x nu are solutii in Z*)
d) Calculam: 2(3x-4)=6x-8
Calculam: 5(2+x)=10+5x
Calculam: 4(x+1)=4x+4
Calculam: 9(2x+3)=18x+27
Rezolvam ecuatia:
6x-8-(10+5x)=4x+4-(18x+27)+5 =>
6x-8-10-5x=4x+4-18x-27+5 =>
x-18=-14x-18 => x=-14x => x=0, x∈Z
