Question

Perimeter of a rectangle is 40cm. If its length is 15cm, then its breadth is​

Answer 1

$\sf\underline{Answer:}$

Perimeter of the rectangle = 40 cm

Length of the rectangle = 15 cm

Let, Breadth of the rectangle be 'b'

$p = 2(l + b)$

$40 = 2(15 + b)$

$20 = 15 + b$

$\boxed{b = 5 \: cm}$

Breadth of the rectangle (b) = 5 cm

Have a good evening ^^

Answer 2

Answer:

${ \underline{ \large{ \pmb{ \sf{Given:}}}}}$

• ${ \sf{Perimeter \: of \: Rectangle = 40cm²}}$
• ${ \sf{Length \: of \: Rectangle = 15 cm}}$

${ \underline{ \large{ \pmb{ \sf{Find:}}}}}$

• ${ \sf{Breadth \: of \: Rectangle}}$

${ \underline{ \large{ \pmb{ \sf{Solution:</p><p>}}}}}$

We know that,

${ \boxed{ \sf{Perimeter \: of \: Rectangle = 2(Length + Breadth) }}}$

$: { \implies{ \sf{perimeter = 2(l + b)}}} \\ \\ : { \implies{ \sf{40 = 2(15+ b)}}} \\ \\ : { \implies{ \sf{40 = 30 + 2b}}} \\ \\ : { \implies{ \sf{2b = 40 - 30}}} \\ \\ : { \implies{ \sf{2b = 10}}} \\ \\ : { \implies{ \sf{b = \frac{10}{2} = 5cm}}} \\ \\ : { \implies{ \sf{b = 5cm}}}$

${ \underline{ \large{ \pmb { \sf{Verification:}}}}}$

${ \sf{40 = 2(l + b)}} \\ \\ { \sf{40 = 2(15 + 5)}} \\ \\ \sf{40 = 2(20)} \\ \\ \sf{40 = 40} \\ \\ \therefore{ \pmb{ \sf{Hence \: Proved}}}$

${ \therefore{ \pmb{ \sf{ Breadth \: of \: Rectangle = 5cm}}}}$