Introduction to Circles

What is the relationship between radius and diameter?

• The diameter is equal to the radius.

• The diameter is half the length of the radius.

• The diameter is twice the length of the radius (Diameter = 2 x Radius).

• The diameter is three times the length of the radius.

What is the area of a circle?

• A = π x Radius²

• A = 2π x Radius

• A = π x Diameter

• A = π x Radius³

What is the formula for the area of a circle?

• A = π x Radius²

• A = 2π x Radius

• A = π x Diameter

• A = π x Radius

What is the formula for the circumference of a circle?

• C = π x Diameter

• C = 2π x Radius

• C = π x Radius^2

• C = 2 x Diameter

How many degrees are in a full circle?

• 180 degrees

• 360 degrees

• 90 degrees

• 270 degrees

What is the circumference of a circle?

• C = π x Diameter

• C = 2π x Radius

• C = π x Radius

• C = 2 x Diameter

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

• The area increases linearly with the radius (A = π x r)

• The area increases with the square of the radius (A = π x r²)

• The area remains constant regardless of the radius

• The area decreases with the square of the radius (A = π x r²)

What is the definition of a semicircle?

• A semicircle is a quarter of a circle, formed by a radius and the arc connecting its endpoints.

• A semicircle is half of a circle, formed by a diameter and the arc connecting its endpoints.

• A semicircle is a full circle divided into two equal parts.

• A semicircle is a shape that has three sides and is not a circle.

What is a secant line?

• A line that intersects a circle at two points.

• A line that is tangent to a circle at one point.

• A line that passes through the center of a circle.

• A line that does not intersect a circle.

What is the central angle of a circle?

• An angle whose vertex is at the center of the circle and whose sides are radii.

• An angle formed by two tangents to the circle.

• An angle that measures 90 degrees.

• An angle formed by two chords in the circle.