Решите уравнения 1) -2х+1+5(х-2)=-4(3-х)=1 2) (х-5)^2 +(х+4)^2=2х^2 3) 5+ х/2=3x+6/5

1) -2х + 1 + 5(х - 2) = -4(3 - х) - 1;

-2х + 1 + 5 * х - 5 * 2 = -4 * 3 - 4 * (-х) - 1;

-2х + 1 + 5х - 10 = -12 + 4х - 1;

-2х + 5х - 4х = -12 - 1 - 1 + 10;

3х - 4х = -12 - 1 - 1 + 10;

-х = -12 - 1 - 1 + 10;

-х = -13 - 1 + 10;

-х = -14 + 10;

-х = -4;

х = 4.

Ответ: х = 4.

2) (х - 5)^2 + (х + 4)^2 = 2х^2;

x^2 - 2 * x * 5 + 5^2 + x^2 + 2 * x * 4 + 4^2 = 2x^2;

x^2 + x^2 - 2x^2 - 10x + 25 + 8x + 16 = 0;

-2x + 41 = 0;

-2x = -41;

x = -41 : (-2);

x = 20,5.

Ответ: х = 20,5.

3) 5 + х/2 = 3x + 6/5;

2 * 5 + 2 * х/2 = 2 * 3х + 2 * 6/5;

10 + х = 6х + 12/5;

х - 6х = 12/5 - 10;

-5х = 12/5 - 50/5;

-5х = -38/5;

х = -38/5 : (-5);

х = -38/5 * (-1/5);

х = 38/25 = 1 13/25.

Ответ: х = 38/25 = 1 13/25.