Answer:
x = 12
∠ABD = 54°
∠CBD = 126°
Step-by-step explanation:
The two marked angles form a straight line, so are a "linear pair." That means their sum is 180°.
∠ABD + ∠CBD = 180°
(4x +6)° +(11x -6)° = 180°
15x = 180 . . . . . . . . . . . . . divide by °, collect terms
x = 12 . . . . . . . . divide by 15
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Angle ABD is (4(12) +6)° = 54°
Angle CBD is (11(12) -6)° = 126°
