Work out the value of the missing angle x.
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Answer:
x = 5°
Step-by-step explanation:
Linear pair: a pair of adjacent angles formed when two lines intersect. The two angles are always supplementary and so their measures sum to 180°.
If the side of a polygon is extended, the angle formed outside the polygon is the exterior angle. The sum of the exterior angles of a polygon is 360°.
Sum of exterior angles:
⇒ 45° + 90° + 25° + 90° + x° + (180° - 140°) + (180° - 115°) = 360°
⇒ 355° + x° = 360°
⇒ x = 5°