Решите уровнение а) 8/25y=3 цел 1/5 б) 1/9z+7/18z-11/27z=2 цел 1/2 в) а-13/18a=1/3 г) 1 цел 5/7x-5/9=2 цел 4/9 д) x-1/x = 6 цел 6/7

а) 8 / 25y = 3 цел 1/5;

8 / 25y = 3 / 5;

25/8 * 8 / 25y = 25/8 * 3 / 5;

y = 3 / 8 * 5;

y = 15 / 8;

б) 1 / 9z + 7 / 18z - 11 / 27z = 2 цел 1 / 2;

1 / 9z + 7 / 18z - 11 / 27z = 1;

216 * 1 / 9z + 216 * 7 / 18z - 11 / 27z * 216 = 216 * 1;

24x + 27 * 7x - 8 * 11x = 216;

24x + 189x - 88x = 216;

125x = 216;

x = 216 / 125;

в) а - 13 / 18a = 1 / 3;

18a - 13a = 6;

5a = 6;

a = 6 / 5;

a = 1,2;

г) 1 цел 5 / 7x - 5 / 9 = 2 цел 4 / 9;

5 / 7x - 5 / 9 = 16 / 9;

45x - 35 = 112;

45x = 112 + 35;

45x = 147;

x = 147 / 45;

x = 49 / 15;

д) x - 1 / x = 6 цел 6 / 7;

x - 1 / x = 36 / 7;

7 (x - 1) = 36x;

7x - 7 = 36x;

7x - 36x = 7;

-29x = 7;

x = - 7 / 29;

x ≠ 0;