Question

4/√16-2√81
a-10/9
b-14/9
c--10/9
d--14/9

Answer 1

$\dfrac{4}{ \sqrt{16} } -2 \sqrt{81} \to \\\\\\ \dfrac{4}{4 } -2.9\to \\\\\\ 1-18\to \\\\ \boxed{-17}$