Question

if the perimeter of a rectangle with 13 cm length is 40 cm then the breadth is​

Answer 1

Answer:

Perimetre = 7 cm

Step-by-step explanation:

Perimetre of rectangle = 2x(l+b)

                         40 cm  = 2x(13+b)

                         40/2     = 13+b

                          20       = 13+b

                           b        =  20-13

                           b        = 7 cm

Answer 2

$\rm{Perimeter\:of\:Rectangle = 2\times (Length + Breadth)}$

$\longrightarrow\rm{40\:cm = 2\times (13\:cm + Breadth)}\longrightarrow\rm{40\:cm = (2\times 13\:cm) + (2\times Breadth)}$

$\longrightarrow\rm{40\:cm = 26\:cm + (2\times Breadth)}\longrightarrow\rm{ 2\times Breadth = 40\:cm - 26\:cm}$

$\longrightarrow\rm{2\times Breadth = 14\:cm}\longrightarrow\rm{Breadth = 14/2\:cm = 7\:cm}$