Question:
Mark (✓) against the correct answer
Reciprocal of $\frac{-7}{9}$ is
(a) $\frac{9}{7}$
(b) $\frac{-9}{7}$
(c) $\frac{7}{9}$
(d) none of these
Solution:
(b) $\frac{-9}{7}$
Reciprocal of $\frac{-7}{9}=\left(\frac{-7}{9}\right)^{-1}$
Now, we have :
$\frac{1}{\left(\frac{-7}{9}\right)}$
$=\frac{9}{-7}$
$=\frac{9 \times-1}{-7 \times-1}$
$=\frac{-9}{7}$