There are two ways to verify whether the value of ( h ) assumed to be equal to 9 satisfies the given equation:
             13 + h = 21
             13 - 13 + h = 21 - 13
              0 + h = 8
              h = 8        Â
              8 ≠9  Â
Â
             13 + ( 9 ) = 21
               22 = 21
               22 ≠21
 3) Conclude: The given value of ( h ) is not a solution of the given equation.