The relation is that the diameter is twice the length of the radius.
To make more proof, look at the attached image below.
Add five to each side, then divide each side by 2. you will get 6.5 in the end
y = -9
Ok so to write the equation of the line you will need the slope and y-intercept. Since we are given two-point we can easily find the slope by using this equation for slope formula:

So now that we have our equation we can just plug in the numbers:

After subtracting you should get:
0/8
Since zero is in the numerator and you can't divide zero by anything, the slope is 0. We still need the y-intercept for the equation however since the slope is 0 there is no need to put anything else.
Then to find the y-intercept all you have to do is plug in one of the coordinatines into the slope equation to solve, for example, using the point (5,-9):

B is the variable for the y-intercept. Also notice how I put 0 as our slope into the equation. Now all you have to do is solve for b. Which you would get b = -9. Since you have your slope and your y-intercept now you just write out your equatoin for the line which is:
y = 0x - 9
**Just write it as
y = -9
l o l
o k
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5x=x-9 and 4x-10y=8
lets graph that on desmos cause I'm too lazy to subsitute it .
it has one answer
It would be 8.5 because all you have to do is add 3 to 2.5 then you’ll get 5.5 then do that one more time.