G1S2- Unit 2.7 / 2.8

area of a circle

A = πr²

sectors

A sector of a circle is a region bounded by an arc of a circle and radii to the endpoints of the arc.

circumscribed

A shape drawn around another shape with the tightest possible fit. The two shapes will never overlap.

inscribe

An inscribed angle is an angle formed by two chords of a circle which share and endpoint.

area of a sector

Area of sector = measure of arc/360 * πr²

relationships between triangles and circles.

Many triangular shapes can be inscribed in a given circle Exactly one circle can be inscribed in a given triangle.

circumcenter

The circumcenter of a triangle is the center of the only circle that can be circumscribed about it. The cirumcenter always falls inside an acute triangle, outside an obtuse triangle, and on the hypotenuse of a right triangle., The point of concurrency of the perpendicular bisectors of a triangle. and the point that is equidistance from the vertices of the triangle. it is always inside the triangle.

incenter

The incenter of a triangle is the center of the one and only circle that can be inscribed in a triangle., Point of Concurrency for Angle Bisector and the point that is equidistance from each side of the triangle (radius of the inscribed circle)

centroid

The point of concurrency of the medians of a triangle