1) (x-2,5) * 4,2=6,3 2) 3,5 * (х+2,25) = 14 3) (1,75+х) : 1,9=2,5 4) (7,1-х) : 3,6=1,5

Решим уравнение.

1) (x - 2,5) * 4,2 = 6,3;

(x - 2,5) = 6,3/4,2;

(x - 2,5) = 2.1/1.4;

(x - 2,5) = 0.3/0.2;

0.2 * (x - 2.5) = 0.3;

0.2 * x - 0.2 * 2.5 = 0.3;

0.2 * x = 0.3 + 0.2 * 2.5;

0.2 * x = 0.8;

x = 0.8/0.2;

x = 8/2;

x = 4.

2) 3,5 * (х + 2,25) = 14;

3.5 * x + 3.5 * 2.25 = 14;

3.5 * x = 14 - 3.5 * 2.25;

3.5 * x = 6.125;

x = 6.125/3.5;

x = 1.75.

3) (1,75 + х) : 1,9 = 2,5;

1.75 + x = 4.75;

x = 7.75 - 1.75;

x = 3.

4) (7,1 - х) : 3,6 = 1,5;

7.1 - x = 3.6 * 1.5;

7.1 - x = 5.4;

x = 7.1 - 5.4;

x = 1.7.