(7+3i)-(3-9i)complex numbers

C

Step-by-step explanation:

For this, you want to treat i like any other variable, and combine like terms. However you need to keep in mind that there is a negative sign before the second set of parentheses. This means everything inside it should have a negative before it. So we can write it like this:

(7 + 3i) - (3 - 9i)

7 + 3i -3 +9i

4 + 12i

Hope that helps!

Divide the volume of the bath tub by the rate at which the hose fills the bath tub.

Time = 262 / 2.06

= 127.184466 hours(round if needed)