Suppose D is a point in the interior of ⦟ABC. If m⦟ABC=20 and m⦟ABD = 4x-4, and m⦟CBD= 2x. What is m⦟CBD?

Answer 1

If you draw this situation out, you notice that m∠ABD and m∠CBD, when added together, gets you m∠ABC through Angle Addition. Thus:

(4x - 4) + (2x) = 20

x = 4

Substituting x back into our expression for m∠CBD:

m∠CBD = 2(4) = 8

Hope this was helpful.

Answer 2