Question

The length and breadth of a rectangle are given as (2x+ 3y) and (x - 4). Find the
area and perimeter of the rectangle.​

Answer 1

Answer:

Area = (2x+ 3y) × (x - 4)

Perimeter = 2×{(2x+ 3y)+(x - 4)}

Answer 2

Answer:

✳ Perimeter of the rectangle = (3x + 3y - 4) units.

✳ Area of the rectangle = (2x² - 8x + 3xy - 12y) units.

SOLUTION

Length of the rectangle = (2x+ 3y) units.

Breadth of the rectangle = (x - 4) units.

DIAGRAM OF THE RECTANGLE

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PERIMETER

Perimeter of the rectangle = 2(l+b) , Where l is the length and b is the breadth of the rectangle.

Here,

l = 2x + 3y

b = x - 4

⇒ Perimeter of the rectangle = 2(2x + 3y + x -4)

⇒ Perimeter of the rectangle = 4x + 6y + 2x - 8

⇒ Perimeter of the rectangle = 6x + 6y -8

Let us divide throughout by 2,

⇒ Perimeter of the rectangle = (3x + 3y - 4) units.

AREA

Area of a rectangle = l×b , Where l is the length and b is the breadth of the rectangle.

Here,

l = 2x + 3y

b = x - 4

⇒ Area of the rectangle = (2x+3y)(x-4)

⇒  Area of the rectangle = (2x² - 8x + 3xy - 12y) units.