1) x-(-6)=8
x=8+(-6)
x= 2
(-5)+(x-1)=-2
x-1 = (-2)-(-5)
x-1 = 3
x=3+1
x=4
8-(x+8)=(-16)-(-26)
8-(x+8)= 10
x+8 =8-10
x+8 =-2
x=(-2)-8
x= -10
2)
-(67+37)-(67+23)
=(-67)-37-67-23
= (-104)-67-23
= (-171)-23
= -194
(-15+21)-(-38)+(15-38)
=(-15)+21-(-38)+15-38
=(-15+15)+21+38-38
= 0 +(38-38)+21
= 0 +0 +21
= 0 +21+15
= 21