Final answer:
To simplify the expression 5 + 51, substitute a numerical value for 'a'. The result is 56.
Step-by-step explanation:
To simplify the expression 5 + 51 by substituting a numerical value for a, we need to replace the variable 'a' with a specific number. However, since the expression does not contain 'a', there is nothing to substitute. Therefore, the expression remains the same: 5 + 51. Evaluating this expression yields a sum of 56.
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