find x if b is the midpoint of the line AC.
AB=6x-6 and BC=72

Answer:
[tex]if \: b \: is \: the \: mid \: point \: then \: \\ ab = bc \\ then \: 6x - 6 = 72 \\ 6x = 72 + 6 \\ 6x = 78 \\ x = \frac{78}{6} \\ x = 13 \\ thank \: you[/tex]
This question is simply about division of line segments.
x = 13
AB = AC
Thus, 6x - 6 = 72
Add 6 to both sides to get;
6x = 78
divide both sides by 6 to get;
x = 13
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