State whether each pair of ratios are are equivalent. (yes or no)
a) 11 : 17 and 17 : 11
b) 15 : 35 and 25 : 45
c) 38 : 19 and 2 : 1

< coa = 150 ( given)

as ba and bc are tangents

so oc and oa is perpendicular to cb and ab respectively because in circle normal passes through centre

so in quadrilateral oabc

< coa + < oab + < ocb + < abc = 360

150 +90+90 + < abc = 360

330 + < abc = 360

< abc = 360 -330 = 30

so < abc = 30

⭐dhruv⭐