The first step is to draw a triangle incorporating all the data given. The triangle is an isosceles triangle with AB as the unequal side and the vertex C containing the unequal angle.
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The angle bisector of the unequal angle of an isosceles triangle is also the perpendicular bisector of the unequal side. Therefore, AE = EB = 1 unit
The length of the perpendicular bisector CE can be found using Pythagoras theorem since triangle BCE is a right angled triangle.
\(CE^2\) + \(EB^2\) = \(BC^2\).
Substituting and simplifying, we have CE = \(\sqrt{48}\).
Observe that triangle DCE is also a right angled triangle. Applying the Pythagoras theorem,
\(\\
CE^2\) + \(ED^2\) = \(CD^2\)
48 + \((EB + BD)^2\) = 64
Therefore,\( (1 + x)^2\) = 16
Expanding the LHS using standard identities, 1 + \(x^2\) + 2x = 16
Or, \(x^2\) + 2x = 15.
Of all the numbers given in the answer options, the only value that satisfies the above equation is 3.
The correct answer option is A.