(5y-1)²-(2y+5)²=0
25y²-10y+1-(4y²+20y+25)=0
25y²-10y+1-4y²-20y-25=0
21y²-30y-24=0
7y²-10y-8=0
a=7, b=-10, c=-8
D=√{(-10)²-4*7*(-8)}=100+224=324=18²
(5y-1)²-(2y+5)²=0
25y²-10y+1-(4y²+20y+25)=0
25y²-10y+1-4y²-20y-25=0
21y²-30y-24=0
7y²-10y-8=0
a=7, b=-10, c=-8
D=√{(-10)²-4*7*(-8)}=100+224=324=18²