Deductive proof Sum of angles in a triangle

The sum of the angles of a triangle is 180.

The sum of the angles of a triangle is 180.

Properties of Parallelogram

i) The opposite sides are parallel.

ii) The opposite sides are equal.

iii) The opposite angles are equal.

iv)  The diagonals bisect one another.

Properties Of Rhombus

i) All four sides are equal.

ii) The opposite sides are parallel.

iii) The opposite angles are equal.

iv)  The diagonals bisect one another at right angles.

v) The diagonals bisect the angles.

NB: In a rectangle, all of the properties of a parallelogram are found and all four angles are right angles. In a square, all of the properties of a rhombus are found and all four angles are right angles.