220 Basic Engineering Mathematics
(a) (b) (c)
(d) (e) (f)
Figure 25.1
A B
D C
Figure 25.2
P Q
S R
P Q
S R
Figure 25.3
W
Z Y
X
Figure 25.4
A
D C
B
Figure 25.5
E
H G
F
Figure 25.6
Trapezium
In the trapeziumEFGHshown in Figure 25.6,
(a) only one pair of sides is parallel.
Problem 1. State the types of quadrilateral shown
in Figure 25.7 and determine the angles markeda
tol
(a) (b) (c)
(d) (e)
A B
x
x
a
D C
E
H G
F
d
c
b
(^408308)
J x K
x
M L
e f
O
Q P
j
i
g h
N
658
528
R
U
T
S
k
358
758
1158
l
Figure 25.7
(a) ABCDis a square
The diagonals of a square bisecteach of the right
angles, hence
a=
90 ◦
2
= 45 ◦
(b) EFGHis a rectangle