There is no difference, 6rs-(-2rs) if you get rid of the parenthesis you are left with 6rs- -2rs and two negatives make a positive therefore the answer will become 8rs... I hope this helps :)
Hope this will help..........
For there to be an infinite number of solutions, the quantity on the left side of the equation must be the same as on the right.
First, distribute the equation to get
6x + 18 = 3xh + 9h
If h = 2, the equation on the right would also be 6x + 18 which would yield the same equation and hence an infinite number of solutions
So the answer is h = 2