Answer: 
This is the same as writing (x-9)^2 + (x-12)^2 = 225
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Explanation:
Any circle equation fits the template of 
The center is (9,12) which tells us the values of h and k in that exact order.
h = 9
k = 12
To find the radius r, we need to find the distance from the center (9,12) to a point on the circle. The only point we know on the circle is the origin (0,0).
Apply the distance formula to find the distance from (9,12) to (0,0)
The distance from (9,12) to (0,0) is 15 units. Therefore, r = 15
An alternative to finding this r value is to apply the pythagorean theorem. The distance formula is effectively a modified version of the pythagorean theorem.
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Since h = 9, k = 12 and r = 15, we can then say:
which is the equation of this circle.
Lets put the numbers in order...
6,7,7,8,8,9,9,10,11,30
Q1 = 7
Q2 = (8 + 9) / 2 = 17/2 = 8.5
Q3 = 10
IQR = Q3 - Q1 = 10 - 7 = 3 <== so the interquartile range is 3
mean absolute deviation...
the mean of our data is 10.5
now we subtract the mean from every data point....and find its absolute value
6 - 10.5 = -4.5.....| -4.5| = 4.5
7 - 10.5 = -3.5.....| -3.5| = 3.5
7 - 10.5 = -3.5.....|-3.5| = 3.5
8 - 10.5 = - 2.5....|-2.5| = 2.5
8 - 10.5 = -2.5....|-2.5| = 2.5
9 - 10.5 = -1.5....|-1.5| = 1.5
9 - 10.5 = -1.5....|-1.5| = 1.5
10 - 10.5 = -0.5..| -0.5| = 0.5
11 - 10.5 = 0.5...|0.5| = 0.5
30 - 10.5 = 19.5..|19.5| = 19.5
now we take the average of these numbers
(4.5+3.5+3.5+2.5+2.5+1.5 + 1.5 + 0.5+0.5+19.5) / 10 =
40/10 = 4 <== ur mean absolute deviation
In summary :
ur interquartie range (IQR) of ur data set is 3
ur mean absolute deviation (MAD) of ur data set is 4
(6+5+6+8+x) / 5 = 6
(25+x) / 5 = 6
5 + x/5 =6
X/5 = 1
X = 5
The answer would be 140,000 :)
765 / 9 = 85
9*100 = 900 but this is too much
900 - 765 = 135
9 goes into 135 15 times (9*10=90 which leaves 45 which is 9*5 so 5+10) so you minus 15 from the 100 that made 900
so 100 - 15 = 85
