1
99:59:59,999 --> 99:59:59,999
We've got 4x square y - 3xy + 25 - the entire expression 9 y square x

2
99:59:59,999 --> 99:59:59,999
+ 7xy - 20. So when we're subtracting this entire expression, that's equivalent to subtracting

3
99:59:59,999 --> 99:59:59,999
each of this terms individually if we didn't have the paranthesis,another way of thinking about it,

4
99:59:59,999 --> 99:59:59,999
we can distribute this negative sign or you could view this as a

5
99:59:59,999 --> 99:59:59,999
negative one times this entire expression and we can distribute it.