Answer:
See proof below
Step-by-step explanation:
Let
. If w=-z, then r=0 and r is real. Suppose that w≠-z, that is, r≠0.
Remember this useful identity: if x is a complex number then
where
is the conjugate of x.
Now, using the properties of the conjugate (the conjugate of the sum(product) of two numbers is the sum(product) of the conjugates):

=
Thus
. From this,
. A complex number is real if and only if it is equal to its conjugate, therefore r is real.
Answer:
52
Step-by-step explanation:
You have 8 eight hours and 416miles, and you need to distribute those 416 miles to eight hours. so 416/8=52
The original expression evaluates to 54.4 as shown in the first working.
_____
For some reason, 3.4 got transcribed to be 1.7 in the 3rd line of the second working. There is no math operation in the expression that requires 3.4 to be divided by 2.
Answer:
= 6/25 Is the correct answer.
Use the proportion inches per miles.
.5 in / 2 miles = 2.75 in / d miles
Hope this helps :)