Hello!
The first step to solving this equation would be to distribute the 8 to x+7 to simplify the equation:
(8*x)+(8*7)=104
8x+56=104
The second step would be to then subtract 56 from both sides to isolate 8x:
8x+56-56=104-56
8x=48
Finally, the last step would be to divide both sides by 8 to solve for x:
8x/8=48/8
x=6
Your final answer would be x=6
Hope this helps, and Happy New Year!