1) 64-144z+108z²-27z³+14z+27z³-10z²-77=0
108z²-10z²+14z-144z+64-77=0
98z²-130z-13=0
D=16900+5096= 21996
z1= (130+√21996)/196= (130+2√5499)/196= (65+√5499)/98
z2= (130-√21996)/196= (65-√5499)/98
2) 125x³+150x²+60x+8-125x³+100x-150x²-21=0
160x=13
x= 13/160