Y - y₁ = m(x - x₁)
y - 5 = -8(x - 2)
y - 5 = -8(x) + 8(2)
y - 5 = -8x + 16
<u> + 5 + 5</u>
y = -8x + 21
Answer:

Step-by-step explanation:
A circle centered at (0,0) with radius r is 
Since your circle has diameter of 12, then its radius is 6. Then 
So a possible answer is: 
If you want to move the location of the center, but keep it on the x-axis, then add or subtract a number to the x, such as this:

The center of this circle would be (-4, 0) which is still on the x-axis.
+8y and -8y cross out.
So the first one is 3x=15
Second one is 2x=10
x=5
Then plug x is one of the equations
2(5)-8y=10
10-8y=10
x=5
y=0