1. The problem is to simplify the expression $5 - 2\sqrt{7}$. 2. This expression consists of a constant term 5 and a term involving a square root, $2\sqrt{7}$. 3. Since these terms are unlike (one is rational and the other irrational), they cannot be combined further. 4. Therefore, the simplified form of the expression is simply $5 - 2\sqrt{7}$. Final answer: $5 - 2\sqrt{7}$