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5. Area, perimeter, and diagonals of a rectangle

The perimeter of a rectangle: The perimeter is the total distance around the outside, that can be created by adding together the length and the breadth of each side.

Let us consider a rectangle

$ABCD$ of length '

$l$ ' units and breadth '

$b$ ' units.

The perimeter of the rectangle is therefore as follows:

Perimeter(

$P$ )

$=$

$(AB + BC + CD + DA)$ units.

$P =$

$( l + b + l + b )$ units.

$P =$

$(2l + 2b)$ units.

$P =$

$2 (l + b)$ units.

Thus, the length of the rectangle given its perimeter is

$l = P/2 - b$ units.

And, the breadth of the rectangle given its perimeter is

$b = P/2 - l$ units.

Area of rectangle: The area of a rectangle is given by multiplying the length and the breadth.

Let us consider a rectangle

$ABCD$ of length '

$l$ ' units and breadth '(b\)' units.

Therefore, the area of the rectangle is as follows:

Area (

$A$ )

$=$ length

$l$

$×$ breadth

$b$ .

Thus, the length of the rectangle given its area is

$l = A/b$ units.

And, the breadth of the rectangle given its area is

$b = A/l$ units.

Diagonals f rectangle: A rectangle has two diagonals they are equal in length and intersect in the middle. The diagonal is the square root of (length squared + breadth squared).

Diagonal

$(d) =$

$\sqrt{l^{2} + b^{2}}$ .

Where '

$l$ ' and '

$b$ ' is the length and breadth of the rectangle.

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5. Area, perimeter, and diagonals of a rectangle

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