Answer:
-b
Step-by-step explanation:
-(a+b) = -a - b
-a -b + a = -b
( the -a + a cancel each other out )
21 songs are rap songs
1/4=7 so 7+7=14+7=21+7=28=(7x4=28-7=21)
(1,2)
(-1,2)
(1,-2)
(-1,-2)
