



 
Hi Timothy, Let me try a different example, x [3, 11] The absolute value notation for an interval is anchored at the middle of the interval. The middle of this interval is (11 + 3)/2 = 14/2 = 7. The length of the interval is 11  3 = 8 units. The interval then stretches from 4 units to the left of the middle to 4 units to the right of the middle.
The distance between x and 7 is x  7 and hence the interval can be written
Let's try another one, x [5, 8] The middle of the interval is (8 + (5))/2 = 3/2 Thus the interval is
Penny  


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