Given the center  and the radius
 and the radius  of a circle, its equation is
 of a circle, its equation is

In your case, the center is (-4,0), and the radius is 2. Plug these values into the generic formula and you'll get the equation.
 
        
             
        
        
        
Answer:-  A.The independent variable is the input variable and should be represented by the x-axis. 
Explanation:-
A. Correct.
B. Not correct.
<u>Reason</u>:- The independent variable is the input variable and should be represented by the x-axis. 
C. Not correct.
<u>Reason</u>:- The dependent variable is the output variable and should be represented by y-axis.
D. Not correct.
<u>Reason</u>:-The dependent variable is the output variable and should be represented by y-axis.
 
        
             
        
        
        
Given:
M=(x1, y1)=(-2,-1), 
N=(x2, y2)=(3,1), 
M'=(x3, y3)= (0,2),
 N'=(x4, y4)=(5, 4).
We can prove MN and M'N' have the same length by proving that the points form the vertices of a parallelogram.
For a parallelogram, opposite sides are equal
If we prove that the quadrilateral MNN'M' forms a parallellogram, then MN and M'N' will be the oppposite sides. So, we can prove that MN=M'N'.
To prove MNN'M' is a parallelogram, we have to first prove that two pairs of opposite sides are parallel,
Slope of MN= Slope of M'N'.
Slope of MM'=NN'.

Hence, slope of MN=Slope of M'N' and therefore, MN parallel to M'N'

Hence, slope of MM'=Slope of NN' nd therefore, MM' parallel to NN'.
Since both pairs of opposite sides of MNN'M' are parallel, MM'N'N is a parallelogram.
Since the opposite sides are of equal length in a parallelogram, it is proved that segments MN and M'N' have the same length.