3) a)2x-7=11 => 2x=18 => x=9 x-8=0 => x=8 b)(x-1)(x+2)=0 => x=1; x=-2 x+2=0 => x= -2 4) a)2x-5=7 => 2x=14 => x=7 d)7x-5=5x+19 =>2x=24 => x=12 b)131+3y=11 => 3y=−120 => y= -40 e)4z-9=z+7 => 3z=16 => z=16/3 c)7t+18=9t => −2t=−18 => t=9 f)2(x-1)+5=2x+3 => 2x+3=2x+3 => x paote lua orice valoare din Z

2x-5=7      7x-5=5x+19 2x=12       7x=5x+19+5 x=12:2      2x=24 x=6           x=24:2                  x=12 131+3y=11 Asta e gresita 4z-9=z+7 4z=z+7+9 4z=z+16 3z=16 z=16:3 z=5 rest 1       7t+18=9t    2(x-1)+5=2x+3   9t-7t=18     2(x-1)+2=2x   2t=18         2x-2+2=2x   t=9             2x=2x  Coroana Plz