Answer: x = 57
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Explanation:
The three angles of any triangle always add to 180
x+67+56 = 180
x+123 = 180
x+123-123 = 180-123 .... subtract 123 from both sides
x = 57
The missing angle is 57 degrees
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Check:
x+67+56 = 57+67+56 = 180
Answer is confirmed.
