SOLUTION: Graph ofy=|x+1|+|2x-1|

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Question 1063800: Graph ofy=|x+1|+|2x-1|
Found 2 solutions by ikleyn, Edwin McCravy:
Answer by ikleyn(52810) About Me  (Show Source):
You can put this solution on YOUR website!
.


Plot y = |x+1| + |2x-1|


On plotting absolute value functions see the lessons
    How to plot functions containing Linear Terms under the Absolute Value sign. Lesson 1
    How to plot functions containing Linear Terms under the Absolute Value sign. Lesson 2
    How to plot functions containing Linear Terms under the Absolute Value sign. Lesson 3
in this site.


Also, you have this free of charge online textbook in ALGEBRA-I in this site
    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this online textbook under the topic
"Plotting Absolute values functions ".


Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
Graph of y=|x+1|+|2x-1|
Here's what you do, step by step:

Set the expressions inside the absolute value bars equal 0,
x+1 = 0        2x-1 = 0
  x = -1         2x = 1
                  x = 1%2F2  
These define three intervals: x < -1, -1 < x < 1/2, and x > 1/2

For x < -1, |x+1| = -(x+1) and |2x-1| = -(2x-1)
so y = -(x+1)-(2x-1) = -x-1-2x+1 = -3x

For -1 < x < 1/2, |x+1| = x+1 and |2x-1| = -(2x-1)
so y = x+1-(2x-1) = x+1-2x+1 = -x+2

For x > 1/2, |x+1| = x+1 and |2x-1| = 2x-1
so y = x+1+2x-1 = 3x-1-2x+1 = 3x

So the graph is this piecewise graph:



So draw the three lines:





Then erase the parts of the three lines that extend 
past their part of the domain:




Edwin