There are two ways to work this out: normal variables or using "imaginary" numbers.
Normal variables:
![(7+2i)(3-i)\\(7*3)+[7*(-i)]+(3*2i)+[2i*(-i)]\\21-7i+6i-2i^{2}\\\\21-i-2i^{2}](https://tex.z-dn.net/?f=%20%287%2B2i%29%283-i%29%5C%5C%287%2A3%29%2B%5B7%2A%28-i%29%5D%2B%283%2A2i%29%2B%5B2i%2A%28-i%29%5D%5C%5C21-7i%2B6i-2i%5E%7B2%7D%5C%5C%5C%5C21-i-2i%5E%7B2%7D)
Imaginary numbers:
Using the result from earlier:
Now since
, then the expression becomes:
Answer:
what is the question
Step-by-step explanation:
Number 8 would be B. Number 9 would be A. Hope this helps! Mark brainliest? :))
Answer:
699(0.90)(1.07)
Step-by-step explanation:
Given that:
Regular cost of couch = $699
Onsale percentage = 10%
Sales tax in purchase = 7%
Final price of couch :
New price at Selling percentage :
Regular price * (discount) * (sales tax percentage)
Regular price * (100% - 10%) * (100 + 7%)
699 * (1 - 0.1) * (1 + 0.07)
699 * 0.90 * 1.07
699(0.90)(1.07)
8.6
Since there is one number before the decimal, we don't have to move the decimal
8.6 * 10^0
Answer 8.6 * 10^0
