8.1-8.3 Flashcards
Converse of Corresponding Angles Postulate
If 2 lines are intersected by a transversal, and corresponding angles are congruent, then the lines are parallel
converse of cointerior angle theorem
If 2 lines are cut by a transversal & cointerior angles are supplementary, then the lines are parallel.
converse of alt interior angle th
If 2 lines are cut by a transversal & alternate interior angles are congruent, then the lines are parallel
Perpendicular & Parallel Th
If 2 lines are perp 2 the same transversal, then they are parallel.
Perp & Transversal Th
If a transversal is perpendicular to one of two parallel lines, then its also perp to the other line.
trapezoid
quadrilateral with only 1 pair of parallel sides
Triangle Sum Th
the sum of the measures of the angles of a triangle is 180
Quadrilateral Sum Th
The sum of the measures of the angles of a quadrilateral is 360.
quadrilateral is parallelogram? th
If both pairs of opp angles of a quadrilateral are equal, then the quadrilateral is a parallelogram.
exterior angle theorem
An exterior angle of a triangle is equal in measure to the sum of its 2 remote interior angles.
definition of similar
Two triangles are similar iff their vertices can be matched up so that corresponding angles are equal & corresponding sides are in proportion.
definition of congruent
2 triangles are congruent iff their vertices can be matched up so tht the corresponding parts (angles & sides) of the triangles r equal in measure.
Triangle Similarity Postulate (AA Post)
If 2 angles of a triangles are equal to 2 angles of another triangle, then the 2 triangles are similar.
how to find any angle of a triangle?
A = 1/2ab sin C
trig
SOH CAH TOA
