Question

the two side of a rectangle are 15cm and 20cm. find the length of its diagonal.​

Answer 1

Answer:

25 cm

Step-by-step explanation:

let ABCD be the rectangle

AB & BC are the adjacent sides of the rectangle

AC is the diagonal

ABC is an right angle triangle with angle B = 90°

(all angles of rectangle are 90°)

AB and BC are the sides of right angle triangle and AC is its hypotenuse

AB = 15 cm

BC = 20 cm

AC = x

using Pythagoras theorem

${x}^{2} = {15}^{2} + {20}^{2} \\ {x}^{2} = 225 + 400 \\ {x}^{2} = 625 \\ x = \sqrt{625} \\ x = 25cm$

the length of the diagonal of rectangle is 25 cm

hope you get your answer

Answer 2

${\mathbf {\blue{S}{\underline{\underline{olution:-}}}}}$

$\mathfrak{\underline{AnswEr:-}}$

• The diagonal of rectangle = 25 cm

$\mathfrak{\underline{Given:-}}$

• The length of rectangle is 15cm.
• The breadth of rectangle is 20cm.

$\mathfrak{\underline{Need\:To\: Find:-}}$

• Find the diagonal of rectangle = ?

${\mathbf {\blue{E}{\underline{\underline{xplanation:-}}}}}$

$\:\:\:\:\dag\bf{\underline \green{Formula\:used\:here:-}}$

$\bigstar{\underline{\boxed{\sf\purple{Diagonal^2 = Length^2 + Breadth^2}}}}$

$\:\:\:\:\dag\bf{\underline \blue{Putting\:the\:values:-}}$

$\longrightarrow \sf {Diagonal^2 = 15^2 + 20^2}$

$\longrightarrow \sf {Diagonal^2 = 225 + 400}$

$\longrightarrow \sf {Diagonal^2 = 625}$

$\longrightarrow \sf {Diagonal = \sqrt{625} }$

$\longrightarrow\large\boxed{\sf{\purple{Diagonal\:=\;25}}}$

$\:\:\:\:\dag\bf{\underline{\underline \pink{Hence:-}}}$

• The diagonal of rectangle is 25 cm.

$\rule{200}{2}$