Circles Flashcard 2

Front

What is the standard equation of a circle with center (h, k) and radius r?

Back

(x - h)² + (y - k)² = r²

Front

What is the center of the circle given by the equation (x - 3)² + (y + 4)² = 25?

Back

(3, -4)

Front

What is the radius of the circle given by the equation (x + 2)² + (y - 1)² = 16?

Back

4

Front

How do you find the diameter of a circle if you know the radius?

Back

Diameter = 2 * Radius

Front

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

Back

The diameter is twice the length of the radius.

Front

What is the equation of a circle with center at the origin and radius 5?

Back

x² + y² = 25

Front

If the equation of a circle is x² + y² = 36, what is the radius?

Back

6

Front

What is the distance formula used to find the distance between two points (x1, y1) and (x2, y2)?

Back

Distance = √((x2 - x1)² + (y2 - y1)²)

Front

What is the area of a circle with radius r?

Back

Area = πr²

Front

What is the circumference of a circle with radius r?

Back

Circumference = 2πr