Equations of Circles

Front

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

Back

(-2, 4)

Front

What is the radius of the circle with the equation (x-5)²+(y+7)²=8?

Back

2√2

Front

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

Back

4

Front

What is the standard equation of a circle?

Back

(x-h)² + (y-k)² = r²

Front

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

Back

10

Front

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

Back

The radius of the circle.

Front

What do the variables 'h' and 'k' represent in the standard equation of a circle?

Back

The x and y coordinates of the center of the circle.

Front

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

Back

Take the square root of the value on the right side of the equation.

Front

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

Back

The diameter is twice the radius.

Front

If the center of a circle is at (3, -2) and the radius is 5, what is the equation of the circle?

Back

(x-3)² + (y+2)² = 25