EQUATIONS OF CIRCLES

Write the equation of a circle with center (h,k) and radius r.

• x^2 + y^2  = r^2
• (x + h)^2 +  (y + h)^2 = r^2
• (x - h)^2 + (y - k)^2 = r^2
• (x - h)^2 - (h - k)^2 = r

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

• (-4, 0)
• (4, 0)
• (4, 1)
• (-4, 1)

The point (-5,6) is on a circle with center (-1,3) write the equation of the circle

• (x+1)² + (y-3)²= 4000

• (x+5)² + (y-0)²= 25

• (x+1)² + (y-3)²= 25

• (x-1)² + (y+3)²= 25

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

• 4
• 2
• 3
• 16

Which graph corresponds to 
(x)²+ (y-6)²=9

• A
• B
• C
• D

Determine the equation of the circle in standard form: x² + y² + 4x + 6y = 36

• (x+2)² + (y+3)² = 49
• (x+2)² + (y+3)² = 13
• (x-2)² + (y-3)² = 49
• (x-2)² + (y-3)² = 13