Problem:
l3x-3l=5
And the l next the 3s are lines
Answers:
1) 10/3
2) -2/3
3) 5/3
4) -8/3
2006-11-27 16:08:57 · 6 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
Plug in each of the four answers. The only one that works is (2), because you get
| 3 (-2/3) - 3 | = 5
| -2 - 3 | = 5
| -5 | = 5
5 = 5
2006-11-27 16:13:51 · answer #1 · answered by sep_n 3 · 0⤊ 0⤋
Hi, hey lines before and after 3's is known as MODULUS of the expression, you read this expression on the left hand side as MOD of 3x-3. This implies whatever be the value of the expression, you will have to take its positive sign.
I give you an simple example:
|x| Now this expression equals { x if x>=0
-x if x<0}
i.e whatever be the value of x, MOD will result in a positive value.
In this case there are two possibilities:
1. you take 3x-3 as positive i.e.
3x-3 = 5
3x=5+3
3x = 8
x = 8/3
2. -(3x-3) = 5
-3x + 3 = 5
3x = 3-5
3x = -2
which impies x = -2/3 which is the answer from your options.
Thus two possible answers for your question
1. 8/3 and 2. -2/3.
So you have to see range of your x and choose the answer.
But if you have options like above, then you will have one answer only which is -2/3
2006-11-28 00:23:21 · answer #2 · answered by abcd_123 2 · 1⤊ 0⤋
Those lines beside the 3s are absolute values. It can have 2 answers. You can solve it like this:
3x-3=5
3x = 8
x = 8/3
OR
3x-3 = -5
3x = -2
x = -2/3
So my answer is the 2nd one. Since there is no 8/3 in the choices.
2006-11-28 00:19:14 · answer #3 · answered by akosundalo2 1 · 1⤊ 0⤋
number 2 -2/3
2006-11-28 00:16:28 · answer #4 · answered by George 4 · 0⤊ 0⤋
-2/3
2006-11-28 00:12:37 · answer #5 · answered by kippie2525 3 · 0⤊ 0⤋
Absolute value(3x - 3) = 5 has two solutions, so
3x - 3 = 5
3x = 2
x = 2/3
or
3x - 3 = -5
3x = -2
x = -2/3
2006-11-28 00:15:06 · answer #6 · answered by Helmut 7 · 0⤊ 1⤋