Respuesta :
Step-by-step explanation:
A° + 142° = 180° (angle on a straight line is 180°)
A° = 180 - 142
A° = 38°
ΔA = 38°
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Step-by-step explanation:
ΔA = 142° = 180° ----(angle sum property)
ΔA = 180° - 142°
ΔA = 38°