The picture below shows the parallelogram formed by the intersection of two pairs of parallel lines?


What is the area of this parallelogram? And the perimeter?


Let ABCD is a parallelogram is formed by two set of parallel lines.

The distance between the two horizontal lines is 3 cm,


The distance between the vertically slanted lines is 2 cm.



Connect the two vertically slanted lines a right-angle triangle is formed.


From the right-angle triangle ABE



AB is the hypotenuse


AE is the opposite side


EB is the Adjacent side to θ


Sin θ = =


θ = 30o


ABE is 30o


From the fig. we can say that C = ABE = 30o


In parallelogram opposite sides are equal


BAD = C


BAD = 30o


BAF = 90o


BAF = BAD + DAF


90o = 30o + DAF


DAF = 60o



From the diagram cos θ =


COS 60o =


DA = 6 cm


We know that AD, AB are the sides of the parallelogram


Perimeter = 2 (AB + AD)


= 2 (4+6)


= 20 CM


Area = side × perpendicular distance to the opposite side


= AB × AF


= 4 × 3 = 12 cm2


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