To find values of the inequality |2x-5| < 10
.
We know that |x-n| = x-n ix x >n and |x-n| = n-x if
x< n.
Therefore |2x-5| = 2x-5 for 2x-5 > 0. Or x
> 5/2.
Therefore or x > 5/2 , |2x-5| < 10
implies 2x-5 < 10
2x-5 < 10 implies 2x-5+5 <
10+5 , as we added equals to both side.
2x <
15.
2x < 15 implies x < 15/2 = 7.5 , as we divided
both sides by positive equals.
Therefore x>2.5
, x < 7.5.
When x < 2.5 ,
|2x-5| < 10 implies 5-2x < 10.
We add 2x to both
sides:
5 < 10 +2x.
5-10 <
10+2x-10.
-5 < 2x
-5/2 <
2x/2
-2.5 < x. Or x >
-2.5.
Therefore x < -2.5 for any x <
=2.5.
Therefore x is in the interval
(-2.5 , 7.5} but the strict inequality does allow x to take boundary
values.
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