Question

a square park has a diagonal walkway from one corner to another if the area of the park is 400 square feet what is the approximate length of the walkway round to the nearest tenth of a foot

Answer 1

if it's square : we have a 20*20 park, thus from Pythagoras's theorem:
20^2+20^2=800
it's diagonal is thus \[\sqrt{800}\]

Answer 2

determine the perimeter of the trapezoid round to the nearest tenth of an inch

Answer 3

again you need to use Pythagoras, I'll let you figure out how.