3<x≤7 ∩ 5≤x≤9
---o*-->x **>x
3 7 5 9
x∈(3; 7] ∩ x∈[5; 9]
o***>x
3 5 7 9
(3; 7] ∩ [5; 9] = [5; 7]
3<x≤7 U 5≤x≤9
---o*-->x **>x
3 7 5 9
x∈(3; 7] ∪ x∈[5; 9]
o***>x
3 5 7 9
(3; 7] ∪ [5; 9] = (3; 9]
3<x≤7 ∩ 5≤x≤9
---o*-->x **>x
3 7 5 9
x∈(3; 7] ∩ x∈[5; 9]
o***>x
3 5 7 9
(3; 7] ∩ [5; 9] = [5; 7]
3<x≤7 U 5≤x≤9
---o*-->x **>x
3 7 5 9
x∈(3; 7] ∪ x∈[5; 9]
o***>x
3 5 7 9
(3; 7] ∪ [5; 9] = (3; 9]
(50 - 15) - 7 = 28