(f) A quadrilateral PQRS with PR as diameter.

In a cyclic quadrilateral PQRS, PQ= 2 units, QR= 5 units, RS=3 units and /_P Q R=60^0, then what is the measure of SP?

The negation of the proposition "If a quadrilateral is a square, then it is a rhombus" is

Write the coordinates of quadrilateral PQRs as shown in the following figure.

ABCD is a rectangle and P,R and S are the mid - points of the AB, BC, CD and DA respectively. Show that the quadrilateral PQRS is a rhombus.

If ABCD is a quadrilateral and E and F are the midpoints of AC and BD respectively, then prove that vec(AB)+vec(AD)+vec(CB)+vec(CD)=4vec(EF) .