equation practice with angle addition
please help

Answer:
∠ CBD = 63°
Step-by-step explanation:
∠ ABC + ∠ CBD = ∠ ABD, substitute values
7x - 9 + 6x + 27 = 96, that is
13x + 18 = 96 ( subtract 18 from both sides )
13x = 78 ( divide both sides by 13 )
x = 6
Thus
∠ CBD = 6x + 27 = 6(6) + 27 = 36 + 27 = 63°