`6) 12-(-3)-(+5)+(-7)+(+12)-(+4)`
`=12+3-5-7+12-4`
`=11`
`7) 14- |-5| - |+7|+ |-3|`
`=14-5-7+3`
`=5`
`8) 5+ |-6 | - |-15 |-(-11)- |4 |`
`=5+ 6 -15 +11- 4`
`=3`
`9) 11-(-7)+ |-13| - |-10| - (-15)`
`=11+7+ 13-10 +15`
`=36`
`10) - |-8 | +(-12)-(-3)-(+7)+ |-9 |`
`= -8-12+3-7+9`
`=-15`