Question

prove that,of all the parallelogram given sides,the parallelogram which is a rectangle has the greatest area?

Answer 1

parallelogram of gratestest area is 255

Answer 2

Hello Mate!

Observe ||gm ABCD whose base is a, side is b and altitude is h. Remember what altitude is? A line falling perpendicular on one side from opposite vertex.

Let me explain,

Since, small triangle is formed, hypotenuse is always longest side so b > h. Right?

ar( ||gm ABCD ) = a × h or ah

Now observe rec. ABCD. Its side b is itself a altitude.

ar( rect. ABCD ) = ab

As told, b > h

Multiplying a in both sides.


ab > ah

ar( rect. ABCD ) > ar( ||gm ABCD )

This means that area of parallelogram will be greatest if its side became itself height ( altitude ) i.e. ||gm ABCD becomes rect. ABCD.

Have great future ahead!