Answer
$-30$
Work Step by Step
RECALL:
(i) The product of two numbers with the same sign is positive.
(ii) The product of two numbers with different signs is negative
To simplify the given expression, multiply the first two numbers first.
Since they have the same sign, their product will be positive.
$=(15)(-2)$
Multiply the final two numbers. They have different signs, so their product is negative.
$=-30$