Х² + 7х + 6 = 0
х1 + x2= -7
х1 × х2 = 6
х1 = -1
х2 = -6
х² + х = 56
х² + х - 56 = 0
х1 + х2 = -1
х1 × х2 = -56
х1 = -8
х2 = 7
3х² + 5х - 2 = 0
D = 25 - 4 × 3 × (-2) = √49 = 7
x1 = -5 + 7 / 2 × 3 = 2 / 6 = 1 / 3
x2 = -5 - 7 / 2 × 3 = -12 / 6 = -2
<span>(x-4)(x+4)+(3x-1)²=x</span>²-16+9x²-6x+1=10x²-6x-15
Y = 0
5 - 4x = 0
4x = 5
x = 5/4
x = 1,25
x = 0
y = 5 - 4*0 = 5 - 0 = 5
Ответ: (1,25 ; 0), (0 ; 5)