Вправи: 1289

1289. Розв’яжіть рівняння:

1) 7х – 5 = 6х + 1;

7x – 6x = 1 + 5;

x = 6.

2) 4х – 3 = 2х + 5;

4x – 2x = 5 + 3;

2x = 8;

x = 4.

3) 9 – 8у = –6у + 3;

6y – 8y = 3 – 9;

–2y = –6;

y = 3.

4) 6m + 3 = 7m + 8;

6m – 7m = 8 – 3;

–m = 5;

m = –5.

5) –9z – 2 = 9z – 2;

–9z – 9z = –2 + 2;

–18z = 0;

z = 0.

6) 4y + 1,7 = –5,3 + 4y;

4y – 4y = –5,3 – 1,7;

0 = –7.

7) 0,7x + 1,6 = –0,1х;

0,7x + 0,1x = –1,6;

0,8x = –1,6;

x = –2.

8) –4,5x – 3 = 2,7x + 15;

–4,5x – 2,7x = 15 + 3;

–7,2x = 18;

x = –2,5.