Solutions Of Triangles - Casio fx-350MS Booklet

CHAPTER 7
EFG is an isosceles triangle in which
Example 1
H. Find
OPERATION
1 . First calculate ∠
FGE
( 1 8
4
)
¡
∠
FGE
So, is equal to 38°.
2 . To determine ° y
cos
1 8 0
=
cos
° y
Hence, cos is approximately -0.788.
PQR
Example 2
Find the length of QR .
OPERATION
QR
1 . Use the formula
sin
7 • 5
sin 5
¡
Hence, the length of

Solutions of Triangles

° y
cos .
. While in COMP/Deg mode, press
0 1
–
=
2
, press
=
– Ans
is a triangle in which ∠
Q
7 5 .
=
to determine QR. While in COMP/Deg mode, press
° °
63 sin 55
sin 6
X
=
5
is approximately 8.16cm.
QR
∠ = °
FEG 104 . FG is produced to
E
104°
y°
F G
0
(180-104)¡2
180-Ans
cos Ans
= ° , ∠ = ° and PR = 7.5cm.
PQR 55 QPR 63
P
63°
7.5cm
55°
R
3
7.5Xsin 63¡sin 55
H
38
142
-0.788010753
8.157885924
19