Equations of Circles

Front

What is the standard equation of a circle?

Back

(x-h)² + (y-k)² = r², where (h,k) is the center and r is the radius.

Front

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

Back

Center (4,3), Radius = 5 units.

Front

In the circle represented by the equation (x-4)²+(y-3)²=25, what is the diameter?

Back

10.

Front

What is the equation of the circle with center (-1, -1) and radius 3?

Back

(x+1)² + (y+1)² = 9.

Front

What is the center of the circle with the equation (x+2)²+(y-4)²=41?

Back

(-2,4).

Front

What does the variable 'r' represent in the equation of a circle?

Back

The radius of the circle.

Front

How do you find the radius from the equation of a circle?

Back

Take the square root of the number on the right side of the equation (r²).

Front

What is the relationship between the diameter and radius of a circle?

Back

Diameter = 2 × Radius.

Front

If the center of a circle is at (0,0) and the radius is 4, what is the equation of the circle?

Back

x² + y² = 16.

Front

What is the general form of the equation of a circle?

Back

x² + y² + Dx + Ey + F = 0.