(2/5) / (3/5 ×х - 1/5 ) - 1/5 = 1/20
Знаменатель не должен быть = 0 :
3/5× х - 1/5 ≠ 0 ⇒ х ≠1/5 : 3/5 ≠ 1/5 * 5/3 ≠ 1/3
(2/5) / ( (3х-1)/5) = 1/20 + 1/5
(2/5) × ( 5/(3х-1) ) = 5/20
2/(3х-1) = 1/4
3х-1 = 2 × 4
3х=8+1
х=9/3
х= 3
(2/3 ) / (5/6 ×х - 1/6) +1/3 =7/9
5/6 × х - 1/6 ≠ 0 ⇒ х≠ 1/5
(2/3) / ( (5х - 1)/6 ) = 7/9 - 1/3
(2/3) × ( 6/(5х-1) ) = 4/9
4/ (5х-1) = 4/9
5х-1 =9
5х=10
х=10/5
х=2
(3/4 ) / (1/8 × х + 3/8) - 1/2 = 5/14
3/4 : (х+3)/8 = 5/14 + 1/2
3/4 × 8/(х+3) = 5/14 + 7/14
6/(х+3) =6/7
6(х+3) = 6*7 |:6
х+3=7
х=7-3
х=4