Answer:
x = 48 ft
Step-by-step explanation:
Triangle DEF is similar to triangle XYZ
10 x 4 = 40 ft
so
12 x 4 = 48 ft
Answer
x = 48 ft
In order to find the circumference, we first need to find the radius. We have the area, so we can find the radius. We set up this equation:

We begin by dividing both sides by pi.
483.76 =

Next, we take the square root of both sides to get the radius.
r = 22.
Next, we plug this into the formula for the circumference, 2 pi r

So, the circumference of this circle is 138.23 units.
10 millions look at the added image