Răspuns:
Explicație pas cu pas:
1. A={ 0, 3, 8 , 14} , B={0, 1, 2, 6, 9}, C={2, 4, 7 , 14}
A U B={0,1,2,3,6,8,9,14}
A U C={0,2,3,4,7,8,14}
B U C={0,1,2,4,6,7,9,14}
A ∩ B={0}
B ∩ C={2}
A \ B={3,8,14}
C \ B={4,7,14}
2. 3x≤9-3
3x ≤6
x≤6/3
x≤2
c) {1, 2}
4. 80/100×20000=16000 locuri ocupate
20000-16000=4000 locuri ramase libere
6. x+y=180°
x=2y
2y+y=180°
3y=180°
y=180°/3
y=60°
x=2×60°
x=120°
7. AOB+BOC+COD+DOA=360°
90°+100°+2x=360°
190°+2x=360°
2x=360°-190°
2x=170°
x=170°/2=85°
8. x=180°-120°30'
x=179°60'-120°30'
x=59°30'
9. AB II CD
-sunt paralele