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Calculate angle X.
60°+51°+3a=180°
3a=180°-111°=69°
a=23
Then,
a+40°+x=180°
23°+40+x=180°
63+x=180°
x=180°-63=117°✓
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3a+60+51=180
3a=180-111
3a=69
a=23
X=180-23-40
X=117
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