CLASS-8
IMPORTANT RULES FOR QUADRILATERAL

SOME IMPORTANT RULES OF QUADRILATERAL –

Rules.1) A parallelogram will be considered as a rectangle if one of its angles will be right angle.

Rules.2) A rectangle will be considered as a parallelogram when its diagonals are equal.

Rules.3) A rhombus will be a parallelogram when its adjacent sides are equal.

Rules.4) If one angle of a parallelogram is a right angle and two equal adjacent sides are equal then it will be considered as a square, A square is both a rectangle and a rhombus.

Rules.5) For a parallelogram,

a)  Area (A) = Base X Height = B X H

                     Area (A)

b)  Base (B) = -------------- =   Area (A) / Height (H)

                    Height (H)

                         Area (A)

c)   Height (H) = ----------------  =   Area (A) / Base (B)

                         Base (B)

                                   1

Rules.6) Area of a Triangle = ---- X Base (B) X Height (H) [Or Altitude]

                                   2