3x-8=17
x = (17+8):3
x = 25/3
15-(27-x)=-9
x = 27-(15+9)
x = -3
-12+(x-7)= -34
x = (-34+12)+7
x = -15
3x-8 = 17
3x = 17+8
3x = 25
x = 25: 3
x = 25/3
15-( 27-x ) =-9
27-x = 15-(-9)
27-x = 24
x = 27-24
x = 3
-12+ ( x-7) =-34
x-7 = -34 - ( -12)
x-7 =-46
x = -46+ 7
x = -39