Question

18. ABCD is a cyclic quadrilateral in which:
(i) BC || AD, ZADC = 110° and ZBAC = 50°. Find ZDAC
(ii) ZDBC = 80° and ZBAC = 40°. Find ZBCD.
(iii) ZBCD = 100° and ZABD = 70° find ZADB.
​

Answer 1

Step-by-step explanation:

(1) Solution

In ∆ADC

ZADC + ZBAC + ZDAC = 180°

110° + 50° + ZDAC = 180°

160° + ZDAC = 180°

ZDAC = 180° - 160°

ZDAC = 20°

(2) ZDBC +ZBAC +ZBCD = 180°

80° + 40° + ZBCD = 180°

120° + ZBCD = 180°

ZBCD = 180° - 120°

ZBCD = 60°

(3) ZBCD + ZABD + ZADB = 180°

100° + 70° + ZADB = 180°

170° + ZADB = 180°

ZADB = 180°- 170°

ZADB = 10°

Hope it helps you

Mark me as brainlist