1. -6 ≤ x < -1 . . . . conjunction
2. x ≤ 6 . . or . . 10 ≤ x . . . . disjunction
3. 7 ≤ x < 12 . . . . conjunction
4. x < -9 . . or . . -3 ≤ x . . . . disjunction
5. 2 ≤ x ≤ 5 . . . . conjunction
6. x ≤ 54 . . or . . 66 ≤ x . . . . disjunction
7. 39 < x ≤ 43 . . . . conjunction
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Your problem statement provided no letters.
Hope this will help..........
Hello,
The sum of angles in a quadrilateral is 360°.
56,1° + 99,4° + 78,2° + x = 360°
233,7° + x = 360°
x = 360° - 233,7° = 126,3°
Bye :)