SOLUTION: | z-1 | = 7z-13

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Question 984843: | z-1 | = 7z-13
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Check for the two possibilities of z-1 being non-negative and being negative.

z-1 non-negative:
abs%28z-1%29=7z-13
z-1=7z-13
-1=6z-13
12=6z
z=2

z-1 NEGATIVE:
abs%28z-1%29=7z-13
Examine on a number line to help this seem sensible-------
-%28z-1%29=7z-13
-z%2B1=7z-13
1=8z-13
8z=1%2B13
8z=14
z=14%2F8
z=7%2F4

CHECK THIS LAST PART---
abs%287%2F4-1%29=7%287%2F4%29-13
abs%287%2F4-4%2F4%29=49%2F4-52%2F4------NOT ACCEPTABLE

Only acceptable is highlight%28z=2%29.