Hi there!
Here are all the steps into isolating "X" :
[tex]\frac{x}{10}[/tex] + 3 = 6 + 1
[tex]\frac{x}{10}[/tex] + 3 = 7
Subtract 3 from each side of the equation
[tex]\frac{x}{10}[/tex] = 4
Multiply each side of the equation by 10
x = 40
There you go! I really hope this helped, if there's anything just let me know! :)