D. The set of all points in a plane that are equidistant from a fixed point.
Answer:
Unique triangle.
Step-by-step explanation:
If you were to draw the triangle, you would've been able to see that one angle is open and that the other 2 were closed.
Answer:
corresponding value of equal matrix is equal
a=10
b= -6
c=3
Step-by-step explanation:
Answer: First Option
Walter needs to make at least 5 more cookies but no more than 40

Step-by-step explanation:
If we call x the number of cookies that Walter needs to make, then we know that the amount of cookies will be:

Then this amount must be greater than or equal to 20 and must be less than or equal to 55 then.
and 
This is:

We solve the inequality for x.

Then the amount of cookies that Walter must make must be greater than or equal to 5 and less than or equal to 40