Решите уравнение а)5у+(8у+9)=100б)х-(50-х)=2в)(18-3х)-(4+2х)=-6г)х+(х+1)+(х+2)=9д)(z-2)+(z-1)+z=-3е)21+(20-4х)-(11-2х)=0

Найдем корешки.

а) 5 * у + (8 * у + 9) = 100;

13 * y + 9 = 100;

13 * y = 100 - 9;

13 * y = 81;

y = 81/13;

б) х - (50 - х) = 2;

x - 50 + x = 2;

2 * x - 50 = 2;

2 * x = 2 + 50;

2 * x = 52;

x = 26.

в) (18 - 3 * х) - (4 + 2 * х) = -6;

18 - 3 * x - 4 - 2 * x = -6;

-5 * x + 14 = -6;

-5 * x = -20;

x = 4.

г) х + (х + 1) + (х + 2) = 9;

3 * x + 3 = 9;

x + 1 = 3;

x = 3 - 1;

x = 2.

д) (z - 2) + (z - 1) + z = -3;

2 * z - 2 - 1 + z = 3;

3 * z - 3 = 3; 

z - 1 = 1; 

z = 2. 

е) 21 + (20 - 4 * х) - (11 - 2 * х) = 0; 

41 - 4 * x - 11 + 2 * x = 0; 

30 - 2 * x = 0; 

2 * x = 30; 

x = 15.