Score: \( 9 / 10 \) Penalty: none Question Express in simplest radical form. \[ -10 \sqrt{5}+\sqrt{80} \]

To express \(-10 \sqrt{5} + \sqrt{80}\) in simplest radical form, we first simplify \(\sqrt{80}\). Notice that: \[ \sqrt{80} = \sqrt{16 \times 5} = \sqrt{16} \cdot \sqrt{5} = 4\sqrt{5} \] Now, we can substitute this back into the expression: \[ -10 \sqrt{5} + \sqrt{80} = -10 \sqrt{5} + 4 \sqrt{5} \] Next, combine the like terms: \[ (-10 + 4) \sqrt{5} = -6 \sqrt{5} \] Thus, the expression in simplest radical form is: \[ -6 \sqrt{5} \]