Answer: x = 5
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Work Shown:
Angle Bisector Theorem
9/(2x-1) = 15/3x
9*3x = 15(2x-1) ... cross multiply
27x = 30x-15
27-30x = 30x-15-30x ... subtract 30x from both sides
-3x = -15
-3x/(-3) = -15/(-3) .... divide both sides by -3
x = 5