<h3>
Answer: x = 4</h3>
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Explanation:
Saying "Points A,B, and C are collinear" means the three points all fall on the same line. For the sake of simplicity, assume the line is horizontal.
Since B is between A and C, we know that the order of the points from left to right is A, B, C.
Through the segment addition postulate, we say,
AB+BC = AC
(x+3) + (x) = 11
x+3+x = 11
2x+3 = 11
2x = 11-3
2x = 8
x = 8/2
x = 4
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Extra info:
Using x = 4, we see that
AB = x+3
AB = 4+3
AB = 7
Note how this adds to BC = x = 4, getting us,
AB+BC = 7+4 = 11
which is the length of segment AC. This confirms AB+BC = AC is true and confirms our answer.
