
two quantities measured in the same units; a:b, a/b 


an equation that equates two ratios. 


the product of the extremes equals the product of the means 


if two ratios are equal, their reciprocals are also equal 


the letters a and d are the extremes of a proportion a:b=c:d 


the numbers b and c are the means of the proportion a:b =c:d 


when there is a correspondence between two polygons such that their corresponding angles are congruent and their corresponding sides are proportional 

Side sideside similarity theorem 

if the lengths of the corresponding sides of two triangles are proportional, then the triangles are similar. 


a transformation that maps every point in a plane to the final image so that the following is true:1. if p is not the center C, then the image point p’ lies on CP. the scale factor k is a positive number such that k=CP’/CP’ and k does not equal 12. if P is the center point C, the P=P’ 


triangles whose measures are 454590 or 306090 


a ratio of the lengths of two sides of a right triangle 

three basic trigonometric ratios 



side opposite angle A over hypotenuse 






the angle your line of sight makes with a line drawn horizontally 


set of all points in a plane equidistant from a given point 


distance from the center to a spot on the circle 




distance across the circle, through its center 


a segment whose endpoints are points on the circle 


a line that intersects a circle in two points 


a line that intersects the circle in exactly one point 


circles with the same center 


consists of all points+ within the circle 


all points outside of the circle 


the point where the line of tangency intersects the circle to which it is tangent 


in a plane, an angle whose vertex is the center of a circle 


an arc of the circle that is less than 180 degrees 


an arc with measure greater than 180 degrees 


the difference between 360 and the minor arc 


an angle whose vertex is the center of the circle and whose sides contain chords of the circle 


the arc that lies in the interior of an inscribed angle and has endpoints on the angle 


all vertices lie on the circle 


a circle that included an inscribed polygon 


is tangent to the circle at an endpoint 


is secant to the circle with an endpoint on the circle 

standard equation of a circle with radius(r) and center(h,k) 



in a plane, it’s the set of all points in a plane that satisfy a given condition or a set of given conditions 

polygon interior angles theorem 

the sum of the measures of the interior angles of a convex ngon is (n2)x i80 

polygon exterior angles theorem 

the sum of the measures of the exterior angles of a convex polygon, one angle at each vertex, is 360 degrees 


the measure of each exterior angle of a regular ngon is 1/n x 360 

area of an equilateral triangle 

is one fourth the square of the lengths of the side times root 3 

center of the polygon and radius of the polygon 

are the radius and center of its circumscribed circle 


the distance from the center of the polygon to any side 

area of a regular polygon 

half the product of apothem a x Perimeter 

central angle of a regular polygon 

an angle whose vertex is the center and whose sides contain two consecutive vertices of the polygon 


measure arc AB over 360 x 2(pi)radius 


region bound by two radii of the circle and their intercepted arc 


number from 0 to 1 that represents the chance an event will occur 


a solid bound by polygons, called faces, that enclose a single region of space 


is a line segment formed by the intersection of two faces 


point where 3 or more edges meet 




tetrahedron, cube, octahedron, dodecahedron, icosahedron 


a polyhedra with 2 congruent faces, called bases 


parallelograms formed by connecting the corresponding vertices of the bases 


all lateral edges are perpendicular to the bases 

surface area of a right prism 



a solid with congruent circular bases that lie in parallel planes 

surface area of a right cylinder 

2B+Ch=2(pi)radius squared + 2 (pi)(r)h 




has a circular base and a vertex that is not in the same plane as the base 

lateral surface of a cone 

consists of all segments that connect the vertex with points on the base edge 






1/3 pi(r)squared x height 


locus of all points in SPACE that are a given distance from a point, called the center of the sphere 


segment from center of sphere to sphere 






two solids with equal ratios of corresponding linear measures, such ash eights and radii, 
