3) 3x-2(2x+1)=5
3x-4x-2=5
-x=5+2
-x=7 |*(-1)
x=-7 ⇒ raspuns corect C
4) [tex]25 x^{2} -( 2x+1)^{2} =[5x-(2x+1)][5x+(2x+1)]=[/tex]
[tex](5x-2x-1)(5x+2x+1)=(3x-1)(7x+1)=(7x+1)(3x-1)[/tex]⇒raspuns corect B
5) 2*2√3+3√3-3*4√3=
4√3+3√3-12√3=-5√3⇒raspuns corect B
6) [tex] A_{tr} = \frac{(B+b)*h}{2} = l_{mijl} *h=10*6=60 cm^{2} [/tex]⇒raspuns corect A