Решить 1) x(x^2-2)=x^3+8 2) (x+5)(x-4)-x^2+18=0 3) (x+7)(x--3)^2=53

1) x(x²-2) = x³ + 8
x³ - 2x = x³ + 8
-2x = 8
x = -4
2) (x + 5)(x - 4) - x² + 18 = 0
x² - 4x + 5x - 20 - x² + 18 = 0
x = 2
3) (x + 7)(x - 7) - (x - 3)² = 53
x² - 49 - (x² - 6x + 9) = 53
x² - 49 - x² + 6x - 9 = 53
6x = 111
x = 18.5