Review: Circle in the Cartesian Plane

Review: Circle in the Cartesian Plane

Equation of Circle

C(0,0)

Standard Form:

 $x^2+y^2=r^2$  

General Form:
 $x^2+y^2-r^2=0$  

Equation of Circle

C( h,k)

Standard Form

 $\left(x-h\right)^2+\left(y-k\right)^2=r^2$  

General Form
 $Ax^2+Bx^2+Cx\ +\ Dy+E=0$  

Multiple Choice

What is the standard form of the circle if C( 1,-2) and r= 10?

•  $\left(x+1\right)^2+\ \left(y-2\right)^2=100$  
  

   $.$  
  

•  $\left(x-1\right)^2+\ \left(y-2\right)^2=100$  

•  $\left(x-1\right)^2+\ \left(y+2\right)^2=100$  

Multiple Choice

What is the general form of a circle if the C (2,0) and r=7?

• 
  

  $x^2+y^2-4x\ -45=0$
  

• $x^2+y^2-4x\ +45=0$

• $x^2+y^2+4x\ -21=0$

Multiple Choice

What is the standard form of a circle if:

C ( -4,3)   $r=\ 5\sqrt{2}$  

•  $\left(x+4\right)^2+\left(y\ -3\right)^2=10$  

•  $\left(x+4\right)^2+\left(y\ -3\right)^2=100$  

•  $\left(x+4\right)^2+\left(y\ -3\right)^2=50$