Решите уравнение:
1. (x+4)^2-x^2=2x+1
2. x(x^2-2)=x^3+8
3. (x+5)(x-4)-x^2+18=0
4. (x+7)(x-7)-(x-3)^2=53
5. x^3-49x=0

1)(x+4)^2-x^2=2x+1 x^2+8x+16-x^2=16+1 x^2+8x-x^2=16+1 6x=-15 x=-15:6 x=-2,5 3)(x+5)(x-4)-x^2+18=0 x^2-4x+5x-20-x^2+18=0 x=2 5)x^3-49=0 x(x^2-49)=0 x1=0 x2=7 x3=-7