<em>4x-79=3x-29</em>
<em>Move the terms with "x" on the left, and the numbers on the right.</em>
<em>4x-3x=79-29</em>
<em>x=50</em>
1/2 because 36 is half of 72. You could also divide the numbers by 12 and you will get 3/6 which is the same as 1/2.
The +k part of the function takes the original function and translates it straight up k units. It's as simple as that. If your function is the line f(x) = 3x, then the function f(x) = 3x + 4 moves that first function up 4 units.