An alternative formula is formula_2 where "d" is the distance between parallel sides, or the height when the decagon stands on one side as base.&lt;br&gt;
ʌ n WORD_BOUNDARY ɔ l t ɜː n ə t ɪ v WORD_BOUNDARY f ɔ ɹ m j ʊ l ə WORD_BOUNDARY ɪ z WORD_BOUNDARY f ɔ ɹ m j ʊ l ə WORD_BOUNDARY t uː WORD_BOUNDARY w ɛ ɹ WORD_BOUNDARY d iː WORD_BOUNDARY ɪ z WORD_BOUNDARY ð ə WORD_BOUNDARY d ɪ s t ə n s WORD_BOUNDARY b ɪ t w iː n WORD_BOUNDARY p æ ɹ ə l ɛ l WORD_BOUNDARY s aɪ d z WORD_BOUNDARY ɔ ɹ WORD_BOUNDARY ð ə WORD_BOUNDARY h aɪ t WORD_BOUNDARY w ɛ n WORD_BOUNDARY ð ə WORD_BOUNDARY d ɪ k æ ɡ ə n WORD_BOUNDARY s t æ n d z WORD_BOUNDARY ɔ n WORD_BOUNDARY w ʌ n WORD_BOUNDARY s aɪ d WORD_BOUNDARY æ z WORD_BOUNDARY b eɪ s WORD_BOUNDARY æ n d WORD_BOUNDARY ɛ l t iː WORD_BOUNDARY b iː ɑ ɹ WORD_BOUNDARY æ n d WORD_BOUNDARY d̠ʒ iː t iː WORD_BOUNDARY