SOLUTION: 4 + /r+2/ = 7

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Question 104564: 4 + /r+2/ = 7
Found 2 solutions by edjones, Fombitz:
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
4+|r+2|=7
|r+2|=3
.
r+2=3
r=3-2
r=1
.
r+2=-3
r=-3-2
r=-5
.
Check:
4+|1+2|=7 true
4+|-5+2|=7 true
.
Ed

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
4+%2B+abs%28r%2B2%29+=+7
4+-+4+%2B+abs%28r%2B2%29+=+7+-+4 Additive inverse of 4.
abs%28r%2B2%29+=+3 Simplify.
The absolute value function is defined as
abs%28x%29=x if x%3E=0 and
abs%28x%29=-x if x%3C0
Since we don't know the value of (r+2), we solve for both cases.
Assume %28r%2B2%29%3E=0, then
abs%28r%2B2%29=r%2B2
r%2B2=3
r=1
Assume %28r%2B2%29%3C0, then
abs%28r%2B2%29=-%28r%2B2%29
-%28r%2B2%29=3
-r-2=3
-r=5
r=-5
Check your answers.
4+%2B+abs%28r%2B2%29+=+7
r=1
4+%2B+abs%281%2B2%29+=+7
4+%2B+abs%283%29+=+7
4+%2B+3+=+7
7+=+7
Good answer.
r=-5
4+%2B+abs%28-5%2B2%29+=+7
4+%2B+abs%28-3%29+=+7
4+%2B+3+=+7
7+=+7
Good answer.