Add or subtract the following (this is algebra for those people who don't know):
1. 4x + 3xy+ -5x = ?
2. 6x + 2y + 5x + -3y = ?
3. 2m + -8m + -4m + -6m = ?
4. -18xy + 9x2y + 4xy + -5x2y = ? (note:the 2 in this number are exponents)
5. a + 2b + 3c + d + 2a + -b + -c + d
Please answer it now im going to need it tommorow (i use Philippine Time)