Jawabanmu

2014-01-26T20:30:46+07:00
1. -19
2. 21
3. 17
4. -55

Maaf kalau salah jawabannya :)

2014-01-26T20:44:55+07:00
10-25+(-4)= (-15)+(-4)= -19 , -17-(-8)+12= -17+8+12= -9+12=3, 18-16-(-15)= 2+15= 17 , -98+(-7)-(-50)= -105+50= -55