1) 299x^+ 100x-500-101x^ 2) (2x-3)(5x+1) = 2x+0.4 3) (x+1)^ =7918-2x

1) 299х^2 + 100х = 500 - 101х^2;

299х^2 + 101х^2 + 100х - 500 = 0;

400х^2 + 100х - 500 = 0.

Поделим уравнение на 100:

4х^2 + х - 5 = 0.

D = b^2 - 4ac = 1 + 4 * 4 * 5 = 81.

x1 = (-b + D)/2a = (-1 + 9)/8 = 8/8 = 1.

x2 = (-b - D)/2a = (-1 - 9)/8 = -10/8 = -1 1/4.

2) (2x - 3) * (5x + 1) = 2x + 0,4;

10x^2 + 2x - 15x - 3 - 2x - 0,4 = 0;

10x^2 - 15x - 3,4 = 0.

D = 225 + 4 * 10 * 3,4 = 361.

x1 = (15 + 19)/20 = 34/20 = 17/10 = 1,7.

x2 = (15 - 19)/20 = -4/20 = -1/5.

3) (x + 1)^2 = 7918 - 2x;

x^2 + 2x + 1 - 7918 + 2x = 0;

x^2 + 4x - 7917 = 0.

D = 16 + 4 * 1 * 7917 = 31684.

x1 = (-4 + 178)/2 = 174/2 = 87.

x2 = (-4 - 178)/2 = -182/2 = -91.