Iam having some issues with absolute value. can someone me understand it ?

That's so easy that you won't believe it !

The absolute value of a number is just the size of it, ignoring whether it's
a positive or negative number.

Negative numbers go down.  Positive numbers go up.  Absolute value is
just how far the number goes, regardless of which direction.

Absolute value is how much money passed between you and the bank,
regardless of whether you put it in or took it out.

Absolute value is how much the airplane's altitude changed, regardless of
whether it climbed or descended.  It's the length of your trip in the elevator,
regardless of whether you were going up or down.

The absolute values of  +492  and  -492  are the same. 
Both numbers are  492  big.

Absolute value just man's the distance it is away from zero. |8| is 8 because it is 8 numbers away from 0.|-8| is also 8 for the same reason.

50.2450.24 in squared