1.
3x^2-4x-1=0
D=(-4)^2-4*3*(-1)=16+12=28
X1,2= 4+-28/6
x1=4+28/6=32/6=5,3
x2=4-28/6=-4
5x^2-178+105=0
D=(-178)^2-4*5*105=31 684-2100=29 584
x1,2=178+-V29 584/10=178+-172/10
х1=178+172/10=35
х2=178-172/10=0,6
2.
3х^2-25x-18/x^2-5x-36
3-5x/2
-5x=-3
x=3/5 /2
x=6/5=1,2