NCM 2nd CE 4B10b e.doc - New Century Mathematics Second...

O
B
C
A
68 
b
D
New Century Mathematics (Second Edition) 4B
10 Basic Properties of Circles
Consolidation Exercise 10B
[ In this exercise, unless otherwise stated, O is the centre of a circle .]
Level 1
Find the unknowns in the following figures. [Nos. 1–18]
1. 2. 3.
4. 5. 6.
7. 8. 9.
© Oxford University Press 2014 Consolidation Exercise 4B10
O
B
C
A
80 
x
O
A
B
C
y
65 
O
A
B C
z
260 
O
A
B
a
110 
C
O
B
C
A
70 
x
O
B
C
A
y
D
E
66 
O
A
B
C
60 
a
O
A
B
C
4 b
b
10
.9

10. 11. 12.
© Oxford University Press 2014 Consolidation Exercise 4B10
O
A
B
C
y
D
140 
O
A
B
C
20 
c
O
A B
C
24 
x
32 
D
10
.10

A
B
C
35 
65 
A
B
C
100 
50 
D
A
B
C
100 
140 
O
13. 14.
15.
16. 17.
18.
19. In each of the following figures, determine whether AC is a diameter of the circle. Explain
your answer.
(a) (b)
20. In the figure,

AOC = 100

and

BOC = 140
