please help me subject math
i'll brainliest if you answer correctly

Step-by-step explanation:
1)
8 + (-4)
= 8 - 4
= 4
2)
-2/3 + (-5/6)
= -2/3 - 5/6
= -4-5/6
= -9/6
= -3/2
3)
(-9) (-12)
= 9 × 12
= 108
4)
-5 + (-5)
= -5 - 5
= - 10
5)
(8) (-4)
= 8 × -4
= -32
6)
(1/2) (2/5)
= 1/2 × 2/5
= 1/5
7)
12 + 14
= 26
8)
(13) (7)
= 13 × 7
= 91
9)
(-3/8) (3/4)
= -3/8 × 3/4
= -9/32