Answer:

Step-by-step explanation:
x is the center of the circle.
the chord of length 12 can be splitted into two parts of 6 length each.
since the radius does not change when it touches another end of the circle, we can safely calculate our radius to be the hypotenuse of the triangle formed by the length of the chord and 3.
The explanation is given in the picture
Answer: y = (x +2)² + 5
<u>Step-by-step explanation:</u>
y = a(x - h)² + k <em>where "a" is the leading coefficient and (h, k) is the vertex</em>
Since we don't know "a", we need to plug in the point (x, y) and the vertex (h, k) to solve for "a": (x, y) = (0, 9) and (h, k) = (-2, 5)
y = a(x - h)² + k
9 = a(0 - (-2))² + 5
9 = a(0 + 2)² + 5
9 = a(2)² + 5
<u>-5 </u> <u> -5 </u>
4 = a(4)
<u>÷4 </u> <u> ÷4 </u>
1 = a
Next, plug in "a" and the vertex (h, k):
y = a(x - h)² + k
y = 1(x +2)² + 5
y = (x +2)² + 5
2/5 would be closer
since 2/5 is 0.4
and 1/3 is 0.333...
You can draw a number line to see how 2/5 ( 0.4) is closest to 0.39