Practical Geometry

• Quadrilateral: A quadrilateral is a four-sided polygon.

For the given quadrilateral ABCD:

• • Possible names of quadrilateral are ABCD, BCDA, CDAB and DABC.
  • AB, CD and BC, DA are the pairs of opposite sides.
  • AB, BC; BC, CD; CD, DA and DA, AB are the pairs of adjacent sides.
  • A, C and B, D are the pairs of opposite vertices. 
  • AC and BD are the diagonals of quadrilateral ABCD.
  • ∠A, ∠C and ∠B, ∠D are pairs of opposite angles. 
  • ∠B, ∠C; ∠A, ∠B; ∠C, ∠D and ∠D, ∠A are the pairs of adjacent angles.

For the given quadrilateral JKLM:

• • Points lying in the interior of the quadrilateral are Q, R, S and O.
  • Points lying in the exterior of the quadrilateral are V and U.
  • Points lying on the boundary of th…