Solving for x:
Start by distributing the numbers outside the parentheses to inside the parentheses:
-1 + 7x + 42 + 6x = 36
Now combine like (similar) terms:
13x + 41 = 36
Subtract 41 from both sides:
13x = -5
Divide both sides by 13:
x =

Therefore, x =
.
Hope this helps! :)