3x²-75=0
x²-25=0
(x-5)(x+5)=0
x1= 5, x2= -5
2x²+8=0
x²+4=0
x∈∅
x²+6x+9=0
(x+3)²=0
x= -3
x²+3x-4=0
D= 9+16= 25
x1= (-3+5)/2= 1
x2= (-3-5)/2= -4
5x²-7=0
x²= 7/5
x1= √(7/5)
x2= -√(7/5)
х^2+6х+9=0
Д=36-4×9=36-36=0
Х=-6/2=-3
3x²-75=0
x²-25=0
(x-5)(x+5)=0
x1= 5, x2= -5
2x²+8=0
x²+4=0
x∈∅
x²+6x+9=0
(x+3)²=0
x= -3
x²+3x-4=0
D= 9+16= 25
x1= (-3+5)/2= 1
x2= (-3-5)/2= -4
5x²-7=0
x²= 7/5
x1= √(7/5)
x2= -√(7/5)
х^2+6х+9=0
Д=36-4×9=36-36=0
Х=-6/2=-3