Д=13*13-4*4=153
√153=3*√17
а)7(3y+8)=6(1-4y)
21y+56=6-24y
21y+24y=6-56
45y=-50
y=- 50/45 = -10/9
б) 4y*4-(5y+4) = - 5
--------------- 2-----
12 8
16y-5y-4 = - 21
------------- ---
11y-4 = -21
-------- ----
2(11y-4)=-21*3
22y-8=-63
22y=8-63
22y=-55
y=-55/22
y=-5/2