Решите уравнение 1) (40+x) * 10=800 2) (x-56) * 9=909 3) x+x+100=28028/14 4 (3x+4x+700=70*16

1) (40 + x) * 10 = 800;

Найдем х.

40 + x = 800/10;

40 + x = 80;

x = 80 - 40;

x = 40.

2) (x - 56) * 9 = 909;

x - 56 = 909/9;

x - 56 = 100 + 1;

x = 100 + 1 + 56;

x = 100 + 57;

x = 157.

3) x + x + 100 = 28 028/14;

x + x + 100 = 2 002;

2 * x + 100 = 2 002;

2 * x = 2 002 - 100;

2 * x = 1 902;

x = 1 902/2;

x = 951.

4) 3 * x + 4 * x + 700 = 70 * 16;

3 * x + 4 * x + 700 = 1 120;

7 * x + 700 = 1 120;

7 * x = 1 120 - 700;

7 * x = 420;

x = 420/7;

x = 60.