Find the measure of the missing angles.

d = 90

e = 81

f = 99

Step-by-step explanation:

First, find e because you can figure it out by vertical angles. 81 and e are vertical so e is 81. To find f, you subtract 180 by 81 because it's a straight line which is 99. So f is 99. To find d, you can use the right angle next to it. 180-90 is 90. So d is 90.

< 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⭐