# Geometry semester 1

 The flashcards below were created by user Anonymous on FreezingBlue Flashcards. Collinear Points on the same line Coplaner points on the same plane Non collinear points not on the same line non coplaner points not on the same plane area of a Rectangle Base x height area of a triangle Base x height / 2 b x h / 2 Area of a parallelagram Base x Height Area of a circle A= Pi(r2) Circumference of a circle C= Pi (d) D= diameter diameter of a circle D=2r r=Radius Complementary angle is equal to : 90 degrees Supplementary angle is equal to : 180 degrees Midpoint formula M = (X1 + X2 / 2 , Y1+ Y2 / 2) Endpoint formula ( X1+ X / 2 = X2 , Y1+ Y / 2 = Y2 ) Distance Formula D = [ ( x1-x2 )2 + ( y1-y2 )2 [ = square root sign Linear pair Two angles that create a line Theorem: All verticle angles are.... Congruent Acute angle Less than 90 degrees Obtuse angle More than 90 degrees Straight angle 180 degrees To bisect an angle is to cut it in half Adjacent angles are next to eachother. no overlapping Conditional Statement A -> B Converse Statement B -> A Inverse Statement Not A -> Not B Contrapositive Statement Not B -> Not A Deductive Reasoning Uses facts to come to a conclusion Inductive Reasoning Uses a pattern to determine a conclusion counter Examples Prove the statement is false(ex. All polygons are squares. Prove wrong: Rectangles etc) Biconditional statement If and only if(ex. If a polygon has three sides than it is a triangle. BICONDITIONAL: A polygon has three sides if and only if {iff} it is a triangle. Perpendicular lines Form A right angle Law of detatchment if hypothesis is true, then conclusion is true Law of Syllagism EX. Conclude that A -> B A->NN->PP->B segments are congruent if and only if: The lengths are equal If the lines are parallel then: The corresponding angles are congruent If two lines are parallel than: The alternate interior angles are congruent If two lines are parallel than: the alternate exterior angles are congruent If two lines are parallel then: The consecutive interior angles are supplentary Slope is Y = Mx + BM= slopeB=y intercept Scalene triangle all different sides Isosceles triangle Two equal sides Equalatrial triangle All sides are equal Equiangular All angles are equal Exterior angle theorum: M<1+M<2= M<3(measure of angle 1 + measure of angle 2 = measure of angle three) 5 congruence thrms SAS: side angle sideSSS: side side sideHL: hypotenuse and legASA: angle side angleAAS: angle angle side if two lines are parallel then their slopes are the same Slope formula Y1-Y2 / X1-X2 Point slope formula Y-Y1=M( X-X1 ) Translation slide reflection flip rotation turn CPCTC Corresponding Parts of Congruent Triangles are Congruent Midsegment of a triangle: Joins the midpoints. 1/2 length of the longest and parallel to longest side Concurrent: Where lines intersect Point of Concurrency The point where lines intersect Circumcenter Lies on a perpendicular bisector Perpendicular bisector perpendicular and bisects a segment incenter Lies on the angle bisector Median of a triangle Joins vertex and midpoint Centroid Lies on medians Altitude of a triangle Joins vertex and perpendicular bisector Ortocenter lies on the altitude Relationship between side lengths and angle measures: longest side opposite largest angle, shortest dise opposite smallest angle AuthorAnonymous ID59086 Card SetGeometry semester 1 DescriptionMcCullough Final Exam Updated2011-01-11T05:37:39Z Show Answers