Решите уровнение а) 8/25y=3 цел 1/5 б) 1/9z+7/18z-11/27z=2 цел 1/2 в)

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