Parts of a Circle, Tangent lines, Incenter and Circumcenter

Front

An angle whose vertex is the center of a circle is a(n) ______.

Back

central angle

Front

Define: INCENTER OF A TRIANGLE

Back

the intersection point of the three angle bisectors of a triangle

Front

What is the definition of a tangent line?

Back

A line that touches a circle at exactly one point.

Front

What is the formula for the circumference of a circle?

Back

C = 2πr, where r is the radius.

Front

What is the relationship between a radius and a tangent line at the point of tangency?

Back

The radius is perpendicular to the tangent line.

Front

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

Back

C = 2π(7) = 14π cm.

Front

What is the circumcenter of a triangle?

Back

The point where the perpendicular bisectors of the sides of the triangle intersect.

Front

How do you find the length of a tangent segment from a point outside the circle?

Back

Use the formula: length = √(distance from point to center² - radius²).

Front

What is the area of a circle with a radius of 5 cm?

Back

A = πr² = π(5)² = 25π cm².

Front

What is the definition of an inscribed angle?

Back

An angle formed by two chords in a circle which have a common endpoint.