How long will the path be.

Given:

The side of the square garden is 30ft.

To find:

The length of the diagonal of the square garden.

Solution:

We know that, the length of the diagonal of a square is

        ...(i)

Where, a is the the side of the square.

We have,

Side of the square garden = 30 ft.

Putting a=30 in (i), we get

The measure of the diagonal path is ft.

Therefore, the correct option is D.