Question

Q5. If one of the angles of a parallelogram is a right angle, Prove that it is a rectangle.
​

Answer 1

we know that opposite angles of a //gm are equal

consider a //gm ABCD

here ∠A=∠C

and   ∠B=∠D

if one of the angle is 90 degree.

let ∠A=90 degree.

⇒∠A=∠C=90 degree.

Now since the sum of angles of quadrilateral is 360 degree.

⇒∠A+∠B+∠C+∠D = 360 degree.

=     90+∠B+90+∠D= 360

=       2∠B=180      (b=D )

∠B=90 degree

⇒  A=B=C=D= 90 degree.

Since ABCD is a // gm its opposite sides are equal.

since each angle is 90 degree and opposite sides are equal

IT FULFILS THE REQUIRED CONDITION OF A RECTANGLE.

HENCE ABCD IS A RECTANGLE.

PROVED.

PLZ DO LIKE AND MARK AS BRAINLIEST . I MADE A LOT OF EFFORT TO HELP U CHAMP!!!!!!

KEEP POSTING......................