I don't know how to do this.
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Answer:
65
Step-by-step explanation:
Angles on a straight line always add up to 180
so we have to find angle BAC by subtracting 180° to 123°
180° - 123° = 57°
Angle BAC = 57°
Angles in a triangle add up to 180°
so we add 57 + 58 = 115°
and the we take 180° - 115 = 65 °
Angle x = 65°