Answer: x = 35
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Step-by-step explanation:
All three angles must add to 180. This is true for any triangle.
x+x+110 = 180
2x+110 = 180
2x = 180-110 ... subtract 110 from both sides
2x = 70
x = 70/2 .... divide both sides by 2
x = 35
As a check: 35+35+110 = 180 which helps confirm the answer.