14а-49а^2=0 7a(2-7a)=0 7a=0 i 2-7a=0 a=0 2=7a a=2/7 2х(х-2)+6(х-2)=0 2x^2-4x+6x-12=0 2x^2+2x-12=0 D=b^2-4ac=2^2-4*2*(-12)=4+96=100 VD=V100=10 x1 = (-2+10)/2*2 = 8/4 = 2 x2 = (-2-10)/2*2 = -12/4 = -3