More with Circles

Front

What is a tangent line to a circle?

Back

A tangent line is a straight line that touches the circle at exactly one point, known as the point of tangency.

Front

Define the term 'secant' in relation to circles.

Back

A secant is a line that intersects a circle at two points.

Front

What is the formula for the circumference of a circle?

Back

The circumference C of a circle is given by the formula C = 2πr, where r is the radius.

Front

How do you find the area of a circle?

Back

The area A of a circle is calculated using the formula A = πr², where r is the radius.

Front

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

Back

The diameter d of a circle is twice the length of the radius r, expressed as d = 2r.

Front

If a circle has a radius of 7, what is its circumference?

Back

C = 2π(7) = 14π, approximately 43.98.

Front

If a circle has a diameter of 10, what is its area?

Back

First, find the radius: r = 10/2 = 5. Then, A = π(5)² = 25π, approximately 78.54.

Front

What is the formula for the area of a sector of a circle?

Back

The area A of a sector is given by A = (θ/360) * πr², where θ is the angle in degrees and r is the radius.

Front

What is the relationship between the angles formed by two tangents drawn from a point outside the circle?

Back

The angle formed between two tangents drawn from a point outside the circle is equal to half the difference of the measures of the intercepted arcs.

Front

How do you calculate the length of an arc in a circle?

Back

The length L of an arc is calculated using the formula L = (θ/360) * 2πr, where θ is the angle in degrees and r is the radius.