Answer:
10 units
Explanation:
Compare the given equation to the standard-form equation for a circle to identify the relevant dimension.
The equation of a circle is written in standard form as ...
(x -h)² +(y -k)² = r² . . . . . . . centered at (h, k) with radius r
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Comparing this to what you are given, you see that ...
h = -25/4
k = 0
r² = 25
The radius is ...
r = √25 = 5
The diameter is twice the radius, so is ...
d = 2r = 2(5)
d = 10
The diameter of the circle is 10 units.