Question

The perimeter of a rectangle is 46 m and its length is 15 m. Find the length of its diagonal in m

Answer 1

Let the breadth of the rectangle $=b$ m.
Perimeter of the rectangle $=2(l+b)=46m=>15+b=23=>b=8m$

The diagonal of a rectangle divides it into two equal right angled triangles. Hence, diagonal forms the hypotenuse of a right angled triangle, with the other two sides being the length and breadth of the rectangle.

Hence, diagonal $=\sqrt{{15}^2+8^2}=\sqrt{289}=17m$