Найдите корни уравнения: 1. x2+10=7x2. x2+6=5x3. x2+4=5x4. x2+4x=55. x2-7x=86. x2-6x-16=07. x2-3x-18=08. x2+5x-14=0

1) х^2 + 10 = 7 х;

х^2 - 7 х + 10 = 0.

D = b^2 - 4ac = 49 - 40 = 9.

x1 = (-b + √D) / 2a = (7 + 3) / 2 = 5;

x2 = (-b - √D) / 2a = (7 - 3) / 2 = 2.

2) x^2 + 6 = 5x;

x^2 - 5x + 6 = 0.

D = 25 - 24 = 1.

x1 = (5 + 1) / 2 = 6;

x2 = (5 - 1) / 2 = 2.

3) x^2 + 4 = 5x;

x^2 - 5x + 4 = 0.

D = 25 - 16 = 9.

x1 = (5 + 3) / 2 = 4;

x2 = (5 - 3) / 2 = 1.

4) x^2 + 4x = 5;

x^2 + 4x - 5 = 0.

D = 16 + 20 = 36.

x1 = (-4 + 6) / 2 = 1;

x2 = (-4 - 6) / 2 = - 5.

5) x^2 - 7x = 8;

x^2 - 7x - 8 = 0.

D = 49 + 32 = 81.

x1 = (7 + 9) / 2 = 8.

x2 = (7 - 9) / 2 = - 1.

6) x^2 - 6x - 16 = 0.

D = 36 + 64 = 100.

x1 = (6 + 10) / 2 = 8;

x2 = (6 - 10) / 2 = - 2.

7) x^2 - 3x - 18 = 0.

D = 9 + 72 = 81.

x1 = (3 + 9) / 2 = 6;

x2 = (3 - 9) / 2 = - 3.

8) x^2 + 5x - 14 = 0.

D = 25 + 56 = 81.

x1 = (-5 + 9) / 2 = 2;

x2 = (-5 - 9) / 2 = - 7.