Question 614990
    a garden in the form of a square is surrounded by a walkway 2m wide. What are the dimensions of the garden if the area of the walkway is 800 square metres?
.
Let x = length of one side of garden
then
(x+4)(x+4)= 800
x^2+8x+16= 800
x^2+8x-784= 0
applying the "quadratic formula" we get:
x = {24.28, -32.28}
throw out the negative solution (extraneous) leaving:
x = 24.28 m
.
details of quadratic follows:
*[invoke quadratic "x", 1, 8, -784 ]