Answer:
64
Step-by-step explanation:
So here you're just completing the square. the equation you gave is simply:
where c is the unknown value we're solving for. Whenever you complete the square, you add (b/2)^2
The reason for this, is because whenever you write a binomial as a perfect square it's in the form:
and this binomial expands out to become: 
If we write the second term of the binomial as b/2 we get:

which simplifies to:

and as you can see the last term is (b/2)^2, which is why we need to add that part for it to be a perfect square.
So we would need to add (16/2)^2 = 8^2 = 64
This way, we can express it as a perfect square binomial:
which expands out to: 
The scale for the second values is 56/8 = 7
C = 3 x 7 = 21
C= 21
Answer:
A(2,2)
Step-by-step explanation:
Let the vertex A has coordinates 
Vectors AB and AB' are perpendicular, then

Vectors AC and AC' are perpendicular, then

Now, solve the system of two equations:

Subtract these two equations:

Substitute it into the first equation:

Then

Rotation by 90° counterclockwise about A(2,2) gives image points B' and C' (see attached diagram)
Given that Cory does not have much money saved he will be using her regular incomes to pay his rent and car, so the most appropiate bank account is a checking account.
That will let him to deposit his incomes and make the payments with checks.
It does not make sense opening an account that pays interests because the money will be spent promptly.
Answer: option a. checking account.