How do you evaluate -7\times 7+ 9\times \frac { - 1} { - 1}?

Feb 28, 2017

$- 40$

Explanation:

$- 7 \times 7 + 9 \times \frac{- 1}{- 1}$

$\therefore = \left(- 7 \times 7\right) + \left(9 \times \frac{- 1}{- 1}\right)$

$\therefore = - 49 + \left(9 \times {\cancel{- 1}}^{1} / 1 \times \frac{1}{\cancel{- 1}} ^ 1\right)$

$\therefore = - 49 + \left(9 \times 1\right)$

$\therefore = - 49 + 9$

$\therefore = - 40$