A landscape artist plans to plant flowers within two concentric circles around a vertical light pole PQ. R is a point on the inner circle and S is a point on the outer circle. R, Q and S lie in the same horizontal plane. RS is a pipe used for the irrigation system in the garden.
The radius of the inner circle is r units and the radius of the outer circle is QS.
The angle of elevation from S to P is 30∘.
RQ^S=2x and PQ=3r
7.1
Show that QS=3r
(3)
7.2
Determine, in terms of r, the area of the flower garden.
