Circle Equations

Write the equation of a circle with center (7, 0) with radius 3.

• $(x-7)^2+y^2=9$

• $x^2+(y-7)^2=9$

• $(x-7)^2+y^2=3$

• $x^2+(y-7)^2=3$

What are the coordinates of the center and the radius of the circle with equation $(x-4)^2+(y-3)^2=25$ ?

• Center  $(4,3)$  
  Radius = 5 units

• Center  $(4,3)$  
  Radius = 25 units

• Center  $(-4,-3)$  
  Radius = 25 units

• Center  $(-4,-3)$  
  Radius = 5 units

Write the standard equation of the circle with the given center and radius; center (0, 0) and radius of 3.

• $x^2+y^2=4$

• $x^2+y^2=81$

• $x^2+y^2=9$

• $x^2+y^2=3$

What is the equation of the circle?

• $(x+1)^2+(y+1)^2=3$

• $(x+1)^2+(y-1)^2=3$

• $(x+1)^2+(y+1)^2=9$

• $(x-1)^2+(y-1)^2=9$

What is the radius of the circle given by the equation $(x-7)^2+(y+3)^2=25$ ?

• 3

• 5

• 10

• 25

What is the diameter of the circle given by the equation $(x-7)^2+(y+3)^2=25$ ?

• 3

• 5

• 10

• 25

The diameter of a circle has length 12. The center is at $(-5,2)$ . Give the equation of the circle.

•  $(x-2)^2+(y+5)^2=36$  

•  $(x-5)^2+(y+2)^2=6$  

•  $(x+5)^2+(y-2)^2=36$  

•  $(x+2)^2+(y-5)^2=6$  

In the equation  $(x-3)^2+(y-2)^2=16$ , the center of the circle is...

•  $(3,2)$  

•  $(-3,-2)$  

•  $(-2,-3)$  

•  $(2,3)$  

In the equation  $(x+2)^2+(y+3)^2=49$ , the center of the circle is at .... 

•  $(2,3)$  

•  $(3,2)$  

•  $(-3,-2)$  

•  $\left(-2,-3\right)$  

In the equation  $(x-3)^2+(y+4)^2=121$  the diameter of the circle is?

• 242

• 11

• 121

• 22