Circle Equations Review

In the equation (x+2)²+(y-3)²=4, the radius of the circle is...

• 4
• 2
• 3
• 16

What is the center and radius for a circle with the equation:
(x-4)²+(y+2)²=25

• C:(4, -2), r=5
• C:(-4, 2), r=5
• C:(4, -2), r=25
• C:(-4, 2), r=25

What is the center of a circle with equation (x-4)² + y² = 5?

• (-4, 0)
• (4, 0)
• (4, 1)
• (-4, 1)

Write the equation of the circle with center C( -5 , 8 ) and radius = 7

• ( x - 5 )² + ( y + 8 )² = 14

• ( x - 5 )² + ( y - 8 )² = 49

• ( x - 5 )² + ( y + 8 )² = 49

• ( x + 5 )² + ( y - 8 )² = 49

The equation of the circle is ( x - 8 )² + ( y + 3 )² = 9 . The center is

• ( 8, -3 )

• ( 8, 3 )

• ( -8, -3 )

• ( -8, 3 )

What is the coordinates of the centre and the radius of the circle with equation:
(x - 1)^2 + (y - 2)^2 = 3^2 ?

• Centre (-1,-2)
  Radius = 3 units
• Centre (1,2)
  Radius = 3 units
• Centre (-1,-2)
  Radius = 9 units
• Centre (1,2)
  Radius = 9 units

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

Rewrite y²-16x²+14y+64x-31=0 in standard form by completing the square.

• (y+7)²/16 - (x+2)²/1=1
• (y+7)²/16 - (x-2)²/1=1
• (y+7)²/84 - (x-2)²/(21/4)=1
• (y+7)² - 16(x-2)²=84

What is the center and radius given the equation, 8x+x²-2y+y²-64=0?

• Center: (-4, 1), Radius: 9

• Center: (4,1), Radius: 9

• Center: (1,-4), Radius: 81

• Center: (-4, 1), Radius: 81

Convert the to standard form.                          x² + y² + 6x - 10y - 15 = 0

• (x + 6)² + (y - 10)² = 15²
• (x + 3)² + (y - 5)² = 19²
• (x + 3)² + (y - 5)² = 7
• (x + 3)² + (y - 5)² = 49