2
а) x² - 7x + 10 = 0
a=1,b=-7,c=10
D=49-40=9
x₁=7+3= 10
x₂= 4
(x-10)(x-4) = 0
б) 5x² + 19x -4 = 0
a=5,b=19,c=-4
D=361+80=441
x₁=-19+21/5=2/5= 0.4
x₂=-19-21/5=-40/5= -8
3
b² - b - 6
9b+18
b² - b - 6 = 0
a=1,b=-1,=-6
D=1+24=25
x₁=1+5= 6
x₂=1-5= -4
(b-6)(b+4)
9(b+2)