Hello,
To solve the equation x + 7 = 13,
We want to subtract 7 from both sides of the equation.
So, we have (x + 7) -7 = x
and 13 - 7 = 6
So on one side of the equation we have x, and on the other side we have 6.
So, we get x = 6.
To check our answer, 6 + 7 = 13, which checks out.
x = 6
Hope this helps!