Using the Distributive Law of Multiplication $$[(a \times b) + (a \times c) = a (b + c)]$$
Let,
a = -8, b = 9, c = 7
Then,
=$$(-8) \times 9 + (-8) \times 7$$
The above equation can be written as,
=$$(-8) \times (9 +7)$$ .....$$[\because (a \times b) + (a \times c) = a \times (b + c)]$$
=$$(-8) \times (16)$$ ..... $$[\because (- \times + = -]$$
$$= -128$$