9514 1404 393
Answer:
2 < x < 24.937
Explanation:
Conceptually, the values of x are allowed to be between those that make angle ABC one of zero measure and that make angle ABD a straight angle.
That is ...
0 < 2x-4 < 180 -86
4 < 2x < 98
2 < x < 49
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However, some study of this geometry convinces us that the largest that angle ABC can be is one that makes ∆ABC isosceles. In that case, AB = CB = DB, and B is the center of the circle through points A, C, and D. Trigonometry can be used to find the value of x in that case.
The radius CB of circle B must be such that the bisector of angle CBD intersects the midpoint of CD:
CB·sin(86°/2) = 14/2
Similarly, the bisector of angle ABC will meet the midpoint of AC:
CB·sin((2x -4)°/2) = 8/2
Equating expressions for CB gives ...
7/sin(43°) = 4/sin((x-2)°)
(x -2)° = arcsin((4/7)sin(43°))
x° = 2° +arcsin(4/7·sin(43°))
x ≈ 24.937
So, a revised upper limit on x puts the range of possible values as ...
2 < x < 24.937