a Calculate to the nearest kilometre the distance between to
(a) Calculate, to the nearest kilometre, the distance between towns W and Y. (b) Calculate, to the nearest degree, the size of the angle marked theta. (c) Calculate, to the nearest kilometre, the distance between towns Y and Z.
Solution
in first triangle angle xwy = 180 - ( 58 + 90 )
= 32 degrees
now finding the length WY
applying law of sines on upper triangle XWY
32 / sin 58 = WY / sin 90
WY = 37.73
distance between towns W and Y is 38 kilometres
b) applying law of sines on bottom triangle WZY and finding angle WYZ
27 / sin Y = 37.73 / sin 90
sin Y = 27 / 37.73
angle WYZ = 45.7 degrees
now angle theta = 180 - ( 90 + 45.7 )
theta = 44 degrees
c) distance between towns Y and Z
applying law of sines
37.73 / sin 90 = YZ / sin 44
YZ = 26
so distance between towns Y and Z is 26 kilometres
