11/21 Circle Review (Math 3)

Front

What is the standard form of a circle's equation?

Back

The standard form of a circle's equation is (x-h)² + (y-k)² = r², where (h,k) is the center and r is the radius.

Front

How do you find the center of a circle from its equation?

Back

To find the center of a circle from its equation in standard form (x-h)² + (y-k)² = r², identify the values of h and k.

Front

In the equation (x-3)² + (y-2)² = 16, what is the center of the circle?

Back

The center of the circle is (3, 2).

Front

What is the relationship between the angles formed by intersecting chords in a circle?

Back

The angles formed by intersecting chords are equal to half the sum of the measures of the arcs intercepted by the angles.

Front

If two chords intersect inside a circle, how do you find the angle formed?

Back

The angle formed is calculated as (arc1 + arc2) / 2, where arc1 and arc2 are the measures of the arcs intercepted by the angle.

Front

What is the measure of arc AD if the angle formed by two intersecting chords is 60°?

Back

If the angle is 60°, then the measure of arc AD is 120° (since the angle is half the measure of the intercepted arc).

Front

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

Back

The measure of an arc can be calculated using the formula: arc measure = (central angle / 360) * circumference of the circle.

Front

What is the measure of arc ABC if it is given as 126°?

Back

The measure of arc ABC is 126°.

Front

What is the formula for the circumference of a circle?

Back

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

Front

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

Back

From the equation (x-h)² + (y-k)² = r², the radius r can be found by taking the square root of the constant on the right side.