A square is a 4-sided regular polygon with all sides equal and all internal angles 90º

**Square Properties.**
Square properties include

(1) diagonals that are congruent,

(2) Each diagonal of a square is the

perpendicular bisector of the other. That is, each cuts the other into two equal parts, and they cross and right angles (90°).

If ABCD is an square and BD=14, find angles x, y and z and DE.

Each diagonal of a square is the perpendicular bisector of the other. That is,

x=45º, y = 90º and z=45º, and DE=7