Question

prove that the interior angle of a regular pentagon is three times the exterior angle of a regular decagon

Answer 1

Heya friend,

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Sum of interior angles of a regular pentagon = 540°

Measure of an interior angle of a regular pentagon = 540°/5 = 108°

Sum of exterior angles of a regular decagon = 360°

Measure of an exterior angle of a regular decagon = 360°/10 = 36°

According to question,

36° × 3 = 108°

108° = 108°
Proved



Thanks

With regards@

Tanisha