Question 20868
In order to isolate the variable you have to get rid of the -13.  To do that you need to +13 to both sides of the equation.  

k-13(+13)=29(+13)  Then do the math. 

The -13 and the +13 equal zero so they cancel each other out leaving just the k on that side of the equation. Then simply add 29+13.

k=42

Of course you can always check that answer.  42-13=29 ???  Yes  :)  

Hope this helps.