Answer:
Step-by-step explanation:
∠CAD is the central angle and ∠CBD is the inscribed/circumference angle which means that
∠CAD = 2(∠CBD)
So, If ∠CBD = 55° then ∠CAD = 110°
Do the foil method. first, outer, inner, last.
He made an error in step 3
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He should have subtracted 2 from both sides.
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