Hello from MrBillDoesMath!
Answer:
Choice D, x = 9
Discussion:
Triangles EFG and EDG are congruent by SAS.
* Side = they both have a side of length 13.
* Angle = base angles F and D are equal as the triangles are isosceles.
Because of that, angles FEG and DEG are equal
*Side = they both share EG
Hence corresponding parts are equal, so FG = DG or
5x - 17 = 3x + 1 => (adding 17 to both sides)
5x - 17 + 17 = 3x + 1 + 17 =>
5x = 3x + 18 => (subtract 3x from both sides)
5x -3x = 18 =>
2x = 18 =>
x = 9
which is choice D
Regards,
MrB