A capital A is also typically used as one of the letters to represent an angle in a triangle, the lowercase a representing the side opposite angle A.
ɐ kˈæpɪɾəl ɐ ɪz ˈɔːlsoʊ tˈɪpɪkli jˈuːzd æz wˈʌn ʌvðə lˈɛɾɚz tə ɹˌɛpɹᵻzˈɛnt ɐn ˈæŋɡəl ɪn ɐ tɹˈaɪæŋɡəl, ðə lˈoʊɚkˌeɪs ɐ ɹˌɛpɹᵻzˈɛntɪŋ ðə sˈaɪd ˈɑːpəzˌɪt ˈæŋɡəl ˈeɪ.