Checking to see if there's an error in my book:
2007-12-29
10:30:30
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12 answers
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asked by
Anonymous
in
Science & Mathematics
➔ Mathematics
1/2x - 3 is below or equal to 1
When I solved it, my answer came out to x is below or equal to 8. My book says the answer is 2 is below or equal to x is below or equal to 8 (2
Reading as:-
(1/2) x - 3 ≤ 1
x - 6 ≤ 2
x ≤ 8
2007-12-29 10:57:51 · answer #1 · answered by Como 7 · 3⤊ 0⤋
Remember that whatever you do to one side of an equation (or inequality) you need to do to both sides. And your goal is to isolate the x.
1/2x - 3 <= 1
Then you need to get the x by itself by adding 3 to each side.
1/2 x - 3 + 3 <= 1 + 3
1/2 x <= 4
Then you need to isolate the x by itself so you need to multiply by the reciprocal 2/1 (2) to get rid of the 1/2.
1/2 x * 2 <= 4 * 2
x <= 8
Go back and check by putting in 8 for x.
1/2 (8) - 3 <= 1
4 - 3 <= 1
1 <= 1
True. Correct.
You said your book says 2 <= x <= 8 ?
If so, then 1 would not work for x, correct? Let's try it.
1/2 (1) -3 <= 1
1/2 - 3 <= 1
-2 1/2 <= 1
True statement. But according to what your book says, 1 should not work. It appears to me your book is incorrect.
2007-12-29 10:43:49 · answer #2 · answered by Chalkbrd 5 · 0⤊ 0⤋
1/2x - 3 = 1
1/2x = 4
x = 2
The first step is to write it out. Then, you add three to each side so that the 3 on the left is cancelled out and 1 becomes 4. The next thing is divide 1/2 by 4 and you get 2. That leaves you with x = 2
2007-12-29 11:23:47 · answer #3 · answered by Anonymous · 0⤊ 2⤋
Could it be your book uses Yahoo! Answers typing language?
1/2x - 3 ≤ 1
1/2x ≤ 4
2x ≥ 1/4
x ≥ 1/8
If you meant: (1/2)(x) - 3 ≤ 1...
x ≤ 8
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EDIT:
It turned out your book made a big mistake. If your book types just way it looked like here, it could've been possible that they were right. It turned out they weren't right for both cases.
2007-12-29 10:35:03 · answer #4 · answered by UnknownD 6 · 0⤊ 0⤋
the book is right. you have to add three to both sides so you get 1/2x is less than or equal to 4. so then u divide both sides by 1/2 and 4 divided by 1/2 is 2!
2007-12-29 10:38:32 · answer #5 · answered by dramageek0117 2 · 1⤊ 1⤋
yes x <= 8
2007-12-29 10:34:01 · answer #6 · answered by holdm 7 · 0⤊ 0⤋
Hmm... I don't know. I got the same answer you got. x is less than or equal to 8.
2007-12-29 10:37:30 · answer #7 · answered by Anonymous · 0⤊ 1⤋
Your answer is right; you can't really have an answer like the one in your book unless you have simultaneous inequalities(two inequalities).
2007-12-29 10:35:05 · answer #8 · answered by nightowl 2 · 0⤊ 0⤋
1/2x - 3 <= 1
1/2x <= 4
x <= 8
Answer: Yes, you're right.
2007-12-29 16:55:14 · answer #9 · answered by Jun Agruda 7 · 3⤊ 1⤋
in general your answer Right unless if there a condition
2007-12-29 10:43:05 · answer #10 · answered by eissa 3 · 0⤊ 0⤋