4t-6 = 24-t

We want only terms with letters on the left and terms without
letters on the right.

So we begin by getting rid of the letter term -t on the right.
So we add its opposite, +t, to both sides like this:

         4t-6 = 24-t
         +t       +t      <--adding opposite +t to both sides
        ------------
         5t-6 = 24

Next we get rid of the term without a letter, -6, on the left.
So we add its opposite, +6, to both sides like this: 

         4t-6 = 24-t
         +t       +t
        ------------
         5t-6 = 24
           +6   +6      <--adding opposite +6 to both sides
        -----------
         5t   = 30

Now that we have only one term with a letter on the
left and only one term without a letter on the right,
we are ready to get rid of the number 5, the 
coefficient of the letter, by dividing:

         4t-6 = 24-t
         +t       +t
        ------------
         5t-6 = 24
           +6   +6
        -----------
         5t   = 30
               <--dividing both sides by 5
              <--canceling 5's on left, dividing on right
          t   = 6      <--that's the solution.

Now we check our solution by substituting (6) for t in the 
original equation:

         4t-6 = 24-t
       4(6)-6 = 24-(6)
         24-6 = 24-6
           18 = 18

Since we get the same number on the left and right, we know that
the answer t = 6 is correct.

Edwin