Answer:
x=16/3
Step-by-step explanation:
left part : -1+3x-8
right part: 7
left part = right part
-1+3x-8=7
left part +8= right part +8
-1 + 3x -8 +8=7+8
-1+3x=15
left part : -1+3x
right part : 15
left part+1=right part+1
-1+3x+1=15+1
3x=16
so
x=16/3