The correct answer choice must correspond to the range shown in the picture: from -5 to 3, inclusive.
Thus, the correct answer must work for EVERY value between -5 and 3, inclusive -- and for no values outside this range.
Plug x=-5 into all of the answer choices.
Eliminate any answer choice in which x=-5 doesn't work.
Answer choice A: |x|≤3
|-5|≤3.
5≤3.
Doesn't work. Eliminate A.
Answer choice B: |x|≤5
|-5|≤5
5≤5.
This works. Hold onto B.
Answer choice C: |x-2|≤3
|-5-2|≤3
7≤3.
Doesn't work. Eliminate C.
Answer choice D: |x-1|≤4
|-5-1|≤4
6≤4.
Doesn't work. Eliminate D.
Answer choice E: |x+1|≤4
|-5+1|≤4
4≤4.
This works. Hold onto E.
Only B and E remain.
Answer choice B -- |x|≤5 -- includes every value from -5 to 5, but the needed range is only from -5 to 3.
Eliminate B.
The correct answer is
E.
Algebraically:
Absolute value means
distance from 0.
Answer choice A: |x|≤3
|x|≤3 means that the value of x cannot be more than 3 places from 0.
Thus, x can be any value between -3 and 3, inclusive:
-3≤x≤3
Answer choice B: |x|≤5
|x|≤5 means that the value of x cannot be more than 5 places from 0.
Thus, x can be any value between -5 and 5, inclusive:
-5≤x≤5.
Answer choice C: |x-2|≤3
|x-2|≤3 means that the value of x-2 cannot be more than 3 places from 0.
Thus, x-2 can be any value between -3 and 3, inclusive:
-3≤x-2≤3
-1≤x≤5 (Solve for x by adding 2 to each part of the inequality.)
Answer choice D: |x-1|≤4
|x-1|≤4 means that the value of x-1 cannot be more than 4 places from 0.
Thus, x-1 can be any value between -4 and 4, inclusive:
-4≤x-1≤4
-3≤x≤5 (Solve for x by adding 1 to each part of the inequality.)
Answer choice E: |x+1|≤4
|x+1|≤4 means that the value of x+1 cannot be more than 4 places from 0.
Thus, x+1 can be any value between -4 and 4, inclusive:
-4≤x+1≤4
-5≤x≤3 (Solve for x by subtracting 1 from each part of the inequality.)
Plugging values into the answer choices seems easier and faster.
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