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MrNeWBiE
Mar15-10, 06:13 AM
1. The problem statement, all variables and given/known data


(1) Express the inequalities x≤3 and 1 ≤ x < 4 in interval notation.


(2) Express in term of inequality: The distance between x and -3 is at least 5.




3. The attempt at a solution

(1) i don't know what he asking for ,,, can you explain it for me please

(2) is it " x+(-3)≥5 " ,,,, x≥2 ? right ?

in (2) he want me to find x or what is the story ?

Mark44
Mar15-10, 09:10 AM
1. Look in your book for some examples of interval notation.
2. Absolute values are used to represent distance.

MrNeWBiE
Mar15-10, 10:43 AM
first one ... done ,,,

2.
it's gone be " abs (x-3) ≥ 5 " then solve for it ?

Mark44
Mar15-10, 12:09 PM
first one ... done ,,,

2.
it's gone be " abs (x-3) ≥ 5 " then solve for it ?

From you problem description, all that is asked for is the expression. You don't need to solve the inequality.

Your expression represents the distance between x and + 3.

Also, there's a key on the keyboard that you can use for absolute values - |

MrNeWBiE
Mar15-10, 12:16 PM
O,O ... how is that ? in the question it's -3 ,,, why in absolute i make it |x+3|≥ 5 ?

Mark44
Mar15-10, 12:32 PM
To find the distance, you subtract, so the distance from x to -3 is represented as is x - (-3).

MrNeWBiE
Mar15-10, 12:42 PM
ahaa