A rectangular field has its centre chosen as the origin of a coordinate system laid on the ground. The positive x-direction points towards the east and the positive y-direction points towards the north.
Five sprinklers are installed at the points P(5,6), Q(−4,7), R(−8,−3), S(9,−5) and T(0,12) (all measurements in metres).
Answer the following:
(a) Identify the quadrant or axis location of each sprinkler.
(b) The caretaker must first visit all the sprinklers that lie in the northern half of the field (i.e.",y>0) and then all those in the southern half. List the sprinklers in the exact order he should visit, starting with the one having the greatest positive abscissa in each half.
(c) Explain, with reference to signs, why no sprinkler installed on the y-axis can ever belong to any quadrant.