Answer:
4 x + 8
Step-by-step explanation:
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As stated in the statement of the question, EF is a bisector of CD, so point G is the median point of CD, so CG = GD
5X - 1 = 7X - 13
X = 6
EF = EG + GF
6X - 4 = EG + 13 x = 6, so
6·6 - 4 = EG + 13
<em>(see attachment)</em>
D
AB=2r
BC=7
AC=AB+BC
-5=2r+7
-12=2r
-6=r
AB=-12