Angles for
An angle whose measure is 90 degrees
What is a right angle?
Two or more lines that lie in the same plane and do not intersect
What are parallel lines?
A five-sided polygon
What is a pentagon?
A triangle with one right angle
What is a right triangle?
A quadrilateral with two pairs of opposite parallel sides
What is a parallelogram?
A segment from the center of a circle to a point on the edge of the circle
What is a radius?
Two or more points that lie on the same line
What are collinear points?
An angle whose measure is less than 90 degrees
What is an acute angle?
Two lines that intersect to form a right angle
What are perpendicular lines?
A polygon whose sides are equal in measure
What is an equilateral polygon?
A triangle with three acute angles
What is an acute triangle?
An equilateral parallelogram
What is a rhombus?
Two points on a circle and the continuous part of the circle between them
What is an arc of a circle?
A unit of measure for angles
What is a degree?
An angle whose measure is greater than 90 degrees
What is an obtuse angle?
Two angles whose measures have the sum of 90 degrees
What are complementary angles?
A polygon in which no diagonal is outside the polygon
What is a convex polygon?
A triangle with one obtuse angle
What is an obtuse triangle?
A quadrilateral with two distinct pairs of consecutive congruent sides
What is a kite?
A line segment whose endpoints lie on the circle
What is a chord?
Lines that are not in the same plane and that do not intersect
What are skew lines?
Two angles with the same measure
What are congruent angles?
Two angles whose measures have the sum of 180 degrees
What are supplementary angles?
A ten-sided polygon
What is a decagon?
A triangle with at least two congruent sides
What is an isosceles triangle?
A quadrilateral with exactly one pair of parallel sides
What is a trapezoid?
Two or more coplanar circles with the same center
What are concentric circles?
A closed geometric figure in a plane in which line segments connect endpoint to endpoint and each segment intersects exactly two others
What is a polygon?
An example that proves a statement wrong
What is a counterexample?
A ray that divides an angle into two congruent angles
What is an angle bisector?
Two sides of a polygon that share a common vertex
What are consecutive sides?
Two angles of a triangle that are opposite two sides of equal length
What are base angles?
An equiangular rhombus or an equilateral rectangle
What is a square?
A line that intersects a circle only once
What is a tangent?
An 11-sided polygon
What is an undecagon?