Answer:
9b) -8 = y
9a) 72° = <em>m</em>∠<em>ABC</em>
Step-by-step explanation:
Since you have an angle trisector, in this case, <em>m</em>∠<em>CBE</em><em> </em>≅ <em>m</em>∠<em>DBA,</em><em> </em>therefore you <em>set</em><em> </em><em>x</em><em> </em>equal to 8, plus, according to Morley's Trisector Theorem, all three angles form an equilateral triangle, so <em>m</em>∠<em>BOC</em><em> </em>also has to equal 24°:

Then, <em>m</em>∠<em>ABC</em><em> </em>comes from multiplying 3 by 24 [three <em>twenty-</em><em>four</em>'s], which results in 72°.
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