Let #A# represent Rico's age. If we write out the process of adding #24# to #A#, then dividing by #2#, then subtracting #6#, and setting that result as equal to #A# in algebraic notation, we get
#A = (A+24)/2-6#
We now wish to solve for #A#. First, we use the fact that
#(a+b)/c = a/c+b/c#
(this is effectively using the distributive property on #1/c(a+b)#).
#A = A/2 + 24/2 - 6#
#=> A = A/2 + 12 - 6#
#=> A=A/2 + 6
Next, we gather all terms which include #A# on one side of the equation by subtracting #A/2# from both sides.
#A-A/2 = 6#
#=>A/2 = 6#
Finally, we multiply by #2# to remove the coefficient of #1/2# from the #A# term.
#A/2 * 2 = 6*2#
#=> A = 12#
It is also good practice to check the final answer by plugging it into the original problem:
#(12+24)/2-6 = 36/2-6 = 18-6 = 12#
As that checks out, we now know that Rico is #12#
