# lines__angles___polygon by lanyuehua

VIEWS: 1 PAGES: 9

• pg 1
Lines, Angles & Polygons

Vocabulary Review
Angle Sizes
 Straight angle: measures 180°
180°

 Right angle: measures 90°

 Acute angle: measures less than 90°

 Obtuse angle: measure is greater than 90° but
less than 180°
Lines
 Perpendicular Lines: 2 lines that intersect at
a right angle

 Parallel Lines: 2 lines in the same plane that
do not intersect

 Transversal: line that intersects 2 parallel
lines
Angle Pairs
 Complementary Angles: Sum of angles is 90°

 Supplementary Angles: Sum of angles is 180°

 Vertical Angles: Form an “X”; have
equal measures
 Alternate Interior Angles: Opposite transversal; inside
parallel lines

 Alternate Exterior Angles:      Opposite transversal;
outside parallel lines
Angles & Angle Pairs

1       2
3       4

5       6
7       8
Polygons
Polygon: Closed figure whose sides are line
segments that intersect only at their endpoints

Regular Polygon: polygon whose sides are all
equal and whose angles are all equal
 Triangles              Quadrilaterals
   Acute Triangle       Trapezoid
   Obtuse Triangle      Parallelogram
   Right Triangle       Rhombus
 Rectangle
 Square
Triangles
 Acute Triangle    all acute angles
 Obtuse Triangle   1 obtuse angle
 Right Triangle    1 right angle
 Trapezoid       1 pair of parallel sides
 Parallelogram   both pairs of opposite sides
parallel
 Rhombus         parallelogram with 4 sides of
equal length
parallelogram with 4 sides of
 Rectangle
equal length and 4 right
angles
parallelogram with all equal
 Square          sides and all right angles