1. The problem is to simplify the expression $\sqrt{x}5 - 2\sqrt{x}6$. 2. We rewrite the expression to clarify it: $5\sqrt{x} - 2\sqrt{x}6$. 3. Recognize that $2\sqrt{x}6 = 2 \times \sqrt{x} \times 6 = 12 \sqrt{x}$. 4. So the expression becomes $5 \sqrt{x} - 12 \sqrt{x}$. 5. Both terms have $\sqrt{x}$ as a common factor, so we factor it out: $(5 - 12) \sqrt{x}$. 6. Simplify inside the parentheses: $5 - 12 = -7$. 7. The simplified expression is $-7 \sqrt{x}$. Therefore, the simplified answer is $-7 \sqrt{x}$.