Sqrt(29-12sqrt5)=|2sqrt5-3|=2sqrt(5)-3
sqrt(6-2sqrt(5))=|1-sqrt(5)|=sqrt(5)-1
sqrt(sqrt(5)-sqrt(5)+1)=sqrt(1)=1
20+5x-6x+15=23-4x
5x-6x+4x=23-20-15
3x=-12
x=-4
7х^2-4х-24=-х^2
8х^2-4х-24=0
Д=в^2-4ас=(-4)^2-4×8×(-24)=16+768=784=корень из784=28
х1=4+28/16=2 х2=4-28/16=-24/16=-3/2
2a{2*(-3);2*2} => 2a{-6;4}
c = 2a -b {-6-1;4+1} => c{-7;5}