To multiply two numbers, you just need to multiply the two values together. In this case, you are multiplying -10.4 by -78.2.
When you multiply two negative numbers, the result is positive. So, (-10.4) multiplied by (-78.2) will give you a positive value.
To multiply the absolute values, ignore the negative signs: 10.4 multiplied by 78.2.
Then, multiply the numbers:
10.4 × 78.2 = 813.28
Since the original numbers were both negative, the final answer will be positive. Therefore, -10.4 × -78.2 = 813.28.