Решите уравнение: -5(5-x)-4x=18 1/3(3x-6)-2/7(7x-21)=9 5,4(3y-2)-7,2(2y-3)=1,2

Найдем корешки.

1) -5 * (5 - x) - 4 * x = 18; 

-25 + 5 * x - 4 * x = 18; 

-25 + x = 18;

x = 18 + 25;

x = 43.

2) 1/3 * (3 * x - 6) - 2/7 * (7 * x - 21) = 9;  

1/3 * 3 * x - 1/3 * 6 - 2/7 * 7 * x + 2/7 * 21 = 9; 

x - 2 - 2 * x + 6 = 9; 

-x + 4 = 9;

-x = 9 - 4;

-x = 5;

x = 5.

3) 5,4 * (3 * y - 2) - 7,2 * (2 * y - 3) = 1,2; 

16.2 * y - 10.8 - 14.4 * y + 21.6 = 1.2; 

1.8 * y + 10.8 = 1.2; 

1.8 * y = 1.2 - 10.8; 

1.8 * y = -9.6; 

y = -9.6/1.8; 

y = -96/18; 

y = -48/9; 

y = -16/3.