Answer:
-1 -9i, where a = -1 and b = -9
Step-by-step explanation:
1st step is to open up the brackets. Since there's a (-) in front of the second bracket, we have to multiply every term by -1, so positive becomes negative, negative becomes positive etc.
4-i-5-8i
Then we collect like terms.
-1 -9i
This is the answer. It looks wrong since the variables are 'positive' in a +bi, but you have to remember that a variable can be represented as a, but its actual value could be negative, in this case -1. This is the same with b, as b could be the same as -9.
This is an expression, so we can't multiply everything by -1 to make it 'look right'. You can only multiply by -1 or 'alter' the terms when the expression equates to something.