Question

║-7+2║
║-2+7║

help plz what must i do when the sticks are there

Answer 1

remove all the negative/positive signs and add normally. This is finding the absolute value. The answer to both ║-7+2║ and ║-2+7║ is 9.

Answer 2

LOL you made my day with 'sticks'...

but those are absolute value signs. 

These are used to signify that whatever comes out of the absolute value cannot be negative. Basically the bars say the total distance of a number away from 0 on the number line. 

$|-a|=a$