B,C,D are all equivalent.
I honestly don’t know
Sorry sweety
Answer: 
Step-by-step explanation:
Given the following Quadratic equation:

You can change its formed by Completing the square.
In order to do Complete the square, you can follow these steps:
1. You can identify that:

2. Then, you can find
. This is:

3. Now you must add
to both sides of the Quadratic equation in order to keep the balance. Then:

4. Finally, simplifying by actoring and adding the like terms, you get:

Answer:
Center
Step-by-step explanation:
A diameter is a line segment whose endpoints are on a circle. It is a special type of chord because it must contain the center of the circle.
Answer:
55 guests
Step-by-step explanation:
131 = 21 + (2x)
subtract 21 from both sides
110 = 2x
x = 55 guests