Answer:
[tex]\boxed {\boxed {\sf D. \ 30 \ feet}}[/tex]
Step-by-step explanation:
The area of a square is found by multiplying the base and the height, but since all the sides are equal, it is equal to multiplying a side by another side.
[tex]a=s*s[/tex]
[tex]a=s^2[/tex]
We know the square garden has an area of 900 square feet. We can substitute this value in for a.
[tex]900 \ ft^2=s^2[/tex]
Since we are solving for the side, we have to isolate the variable s. It is being squared. The inverse of a square is the square root, so we take the square root of both sides.
[tex]\sqrt {900 \ ft^2}= \sqrt{s^2}[/tex]
[tex]\sqrt {900 \ ft^2}=s \\[/tex]
[tex]30 \ ft=s[/tex]
One side of the garden is equal to 30 feet and choice D is correct.
