GEOMETRY

POINT Has no size, only location A

LINE Continues without end in opposite directions. You can name a line by using two points on the line. A B AB

PLANE A flat surface that extends indefinitely in four directions.

PARALLEL LINES Lines in the same plane that do not intersect.

ANGLE is made up of two lines with a common endpoint called the vertex. O VERTEX M P <OMP or <PMO

RIGHT ANGLE Measures exactly 90° W X Z <WXZ or <ZWX

OBTUSE ANGLE Measures greater than 90° and less than 180° U K T <UTK or <KTU

STRAIGHT ANGLE Measures exactly 180° C R B <CBR or < RBC

PERPENDICULAR Lines that intersect to form right angles.

COMPLEMENTARY ANGLES Two angles, the sum of whose measures is 90°. R S <RTS and <STU are complementary angles T U

SUPPLEMENTARY ANGLES Two angles, the sum of whose measures is 180 I G D F <DGI and <IGF are supplementary angles

TRANSVERSE LINES Intersect a pair of parallel lines. <s 1 & 2 and <s 7 & 8 are outside the parallel lines. They are exterior angles. 1 2 7 8

<s 3,4,5, and 6 are inside the parallel lines <s 3,4,5, and 6 are inside the parallel lines. They are called interior angles. 3 4 5 6

CONGRUENT ANGLES Angles that have the same measure.

ACUTE TRIANGLE A triangle with three acute angles.

OBTUSE TRIANGLE A triangle with one obtuse angle.

RIGHT TRIANGLE A triangle that has one right angle.

EQUILATERAL TRIANGLE A triangle with three congruent sides and three congruent angles.

ISOSCELES TRIANGLE A triangle that has two congruent sides.

SCALENE TRIANGLE A triangle with no congruent sides.

POLYGON A closed shape formed by line segments that do not cross.

CONVEX POLYGON A rubber band can fit tightly around this figure.

PARALLELOGRAM A quadrilateral with both pairs of opposite sides parallel.

RECTANGLE A parallelogram with four right angles.

RHOMBUS A parallelogram with four congruent sides.

SQUARE A rectangle with four congruent sides.

TRAPEZIUM A quadrilateral with exactly one pair of parallel sides.