Answer: x = 10
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Segment BD bisects angle ABC, so angle ABC is cut in half by BD. This means the pieces ABD and DBC are congruent angles
(angle ABD) = (angle DBC)
(x) = (4x-30)
x = 4x-30
x-4x = -30
-3x = -30
x = -30/(-3)
x = 10
