unit 1 Flashcards
(21 cards)
plane
flat surface made up of 3 non-collinear points
postulate
The sum of the measures of the parts = the whole
complementary angles
2 angles that = 90°
supplementary angles
2 angles that = 180°
Linear pair
2 adjacent angles whose non common sides opposite rays
triangle angle sum theorem
the sum of the measures of the angles of a triangle = 180°
exterior angle theorem
exterior angle of a triangle is equal to the sum of the two non - adjacent angles
scalene triangle
no congruent sides
isosceles triangle
2 congruent sides
Equilateral triangle
3 congruent sides
Acute triangle
3 acute angles
Right triangle
1 right angle
Obtuse triangle
One obtuse angle
Equiangular
3 = angles
Ordering angles/sides
The smallest angle is opposite the shortest side & the largest angle is opposite the largest side
Triangle inequality
The sum of any 2 sides of a triangle is greater than the length of the 3rd side
Circumcenter
Point of concurrency for perpendicular bisectors in a triangle
Incenter
Point of concurrency for angle bisectors in a triangle
Orthocenter
Point of concurrency for the altitudes in a triangle
Centroid
Point of concurrency for medians in a triangle
auxiliary line
A line or segment added to a diagram to help in solving a problem or providing a concept
