If contact lenses cost 80$ how much will they cost if they are with 10% off?

10% of 80 = 8

80 - 8 = 72

if they are 10% off, the contact lenses will cost $72

< 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⭐