Step by Step Solution

Step 1 :Equation at the end of step 1

  (h • (2a - 7b)) -  3k • (2a - 7b)

Step 2 :Equation at the end of step 2

  h • (2a - 7b) -  3k • (2a - 7b)

Step 3 :Pulling out like terms
 3.1      Pull out     2a-7b 

After pulling out, we are left with :
      (2a-7b) • ( h  *  1 +( 3k  *  (-1) ))

Final result :

  (2a - 7b) • (h - 3k)