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Geometery Flashcards

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69650544AA Similarity PostulateIf two angles of one triangle are cnogruent to two angels of another triangle, then the triangles are similar.
69650545SAS Similarity TheoremIf an angel of one triangle is congruent to an angle of another triangle and the sides including those angles are in proportion, then the triangles are similar.
69650546SSS Similarity TheoremIf the sides of two triangles are in proportion, then the triangles are similar.
69650547Corollary (Theorem 7-3)If three parallel lines intersect two transversals, then they divide the transversals proportionally.
69650548Triangle Angle- Bisector TheoremIf a ray bisects an angel of a triangle, then it divides the opposite side into segments proportional to the other two sides.
69650549Theorem 8-1If the altitudes is drawn to the hypotenuse of a right triangle, then the two triangles formed are similar to the original triangle and to each other.
69650550Corollary 1 & Corollary 2 (to Theorem 8-1)1. When the altitude is drawn to the hypotenuse of a right triangle, the length of the altitude is the geometetic mean between the segments of the hypotenuse. 2. When the altitude is drawn to the hypotenuse of a right triangle, each leg is the geometric mean between the hypotenuse and the segment of the hypotenuse that is adjacent to that leg.
69650551Pythagorean TheoremIn a right triangle, the square of the hypotenuse is equal to the sum of the squares of the legs.
69650552Theorem 8-3If the square of one side of a triangle is equal to the sum of the squares of the other two sides, then the triangles is a right triangle. ---- If c2=a2+b2, then M
69650553Theorem 8-4**If c²
69650554Theorem 8-5**If c²>a²+b², then m∠C >90, and ΔABC is obtuse.
6965055545'-45'-90' TheoremIn a 45°-45°-90° Triangle, the hypotenuse is √2 times as long as a leg.
6965055630'-60'-90' TheoremIn a 30°-60°-90° Triangle, the hypotenuse is twice as long as the shorter leg, and the longer leg is √3 times as long as the shorter leg.
69650557Theorem 9-1If a line is tangent to circle, then the line is perpendicular to the radius drawn to the point of tangency.
69650558Corollary (Theorem 9-1)Tangets to a circle from a point are congruent
69650559Theorem 9-2If a line in the plane of a circle is perpendicular to a radius at its outer endpoint, then the line is tangent to the circle.
69650560Arc Addition PostulateThe measure of the arc formed by two adjacent arcs is the sum of the measures of these two arcs.
70195365Theorem 9-3In the same circle or in congruent circles, two minor arcs are congruent if and only if their central angles are congruent.
70195366Theorem 9-4In the same circle or in congruent circles: (1) Congruent arcs have congruent chords (2) Congruent chrods have congruent arcs.
70195367Theorem 9-5A diameter that is perpendicular to a chord biscets the chord and its arc.
70195368Theorem 9-6In the same circle or in congruent circles: (1) Chrods equally distant from the center(or centers) are congruent. (2) Congruent chords are equally distant from the center(or centers)
70195369Theorem 9-7The measure of an inscribed angle is equal to half the measure of its intercepted arc.
70195370Theorem 9-7 Corollary1. If two inscribed angles intercept the same arc, then the angles are congruent. 2. An angle inscribed in a semicircle is a right angle. 3. If a quadrilateral is inscribed in a circle, them its opposite angles are supplementary
70195371Theorem 9-8The measure of an angle formed by a chord and a tangent is equal to half the measure of the intercepted arc
70195372Theorem 9-9The measure of an angle formed by two chords that intersect inside a circle is equal to half the sum of the measure of the intercepted arcs.
70195373Theorem 9-10The measure of an angle formed by two secants, two tangents, or a secant a tangent drawn from a point outside a circle is equal to half the diffrence of the measures of the intercepted arcs.
70195374Theorem 9-11when two chords interscet inside a circle, the product of the segments of one chord equals the product of the segments of the other chord.
70195375Theorem 9-12when two secants segments are drawn to a circle from an external point the product of one secant segments and its external segments equals the product of the other secant segment and its extreanl segments.
70195376Theorem 9-13when a secant and a tangent segment are drawn to a circle from an external to the square of the tangent segment.
70195377Construction 1Given a segment construct a segment congruent to the given segment.
70195378Construction 2Given an angle construct an angle congruent to the given angle.
70195379Construction 3Given an angle, construct the bisector of the angle
70195380Construction 4Given a segment constuct the perpendicular bisector of the segment.
70195381Construction 5Given a point on a line, construct the perpendicular to the line at the given point.
70195382Construction 6Given the point outside a line, construct the perpendicular to the line from the given point
70195383Construction 7Given a point outside the line construct the parallel to the given line through the given point
70195384Theorem 10-1The bisector of the angles of a triangle intersect in a point that is equidisant from the three sides of the triangle
70195385Theorem 10-2The perpendicular bisector of the sides of a triangle intersect in a point that is equidisant from the three vertices of the triangle
70195386Theorem 10-3The lines that contian the altitudes of a triangle intersect in a point.
70195387Theorem 10-4The medians of a triangle intersect in a point that is two thirds of the distance from each vertex to the midpoint of the opposite side.
70195388Construction 8Given a point on a circle construct the tangent to the circle at the given point
70195389Construction 9Given a point outside a circle construct a tangent to the circle form the given point
70195390Construction 10Given a triangle, circumscribe a circle about the triangle
70195391Construction 11Given a triangle inscirbe a circle in the triangle
70195392Construction 12Given a segment divide the segment into a given number of congruent parts.
70195393Construction 13Given three segments, construct a fourth segment, so that the four segments are in proportion.
70195394Construction 14Given two segments construct their geometric mean.
70195395Postulate 17The area of a square is the square of the lenght of a side, (A=s²)
70195396Area Congruence Postulateif 2 figures are congruent, then they have the same area
70195397Area Addition PostulateThe area of a region is the sum of the areas of its nonoverlapping parts.
70195398Theorem 11-1The area of a rectangle equals teh product of its base and height.(A=bh)
70195399Theorem 11-2The area of a parallelogram equals the product of a base and the height to the base(A=bh)
70195400Theorem 11-3The area of a triangle equals half the product of a base and the height to that base (A=½bh)
70195401Theorem 11-4The area of a rhombus equals half the product of its diagonals(A=½d1d2)
70195402Theorem 11-5The area of the trapezoid equals half the product of the height and the sum of the base (A=½h(b1+b2)
70195403Theorem 11-6the area of a regular polygon is equal to half the product of the apothem and the perimeter.(A=½ap)

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