Chap 3 - lines, angles, shapes Flashcards
define supplementary
add up to 180
define complimentary
add up to 90
angle of circle
360
define vertex
where 2 lines meets, the angle point
define perpendicular
intersect as 90
define vertically opp angles
opp angles are same
define parallel
-lines that never meet
-have arrows
define corresponding angles
same angles on diff lines
define alternate interior angles
same angles inside Z shape
define alternate exterior angles
-same angles outside Z shape
-vertically opp of alternate interior angles
define co-interior angles
-angles in Z add up to 180 (supplementary)
-C shape
define revolution
360, full circle
define obtuse angle
over 90, less 180
define reflex
more 180, less 360
define straight line
180
define right angle
90
how to name angles
vertex in middle btw ends
define acute angle
less 90
how to measure angles
-use protractor
-make a straight line from vertex if needed
define angles around a point
they all add up to 360
define scalene triangle
-no equal sides
-no equal angles
define isosceles triangle
-2 equal side lengths
-angles at bases are equal
define acute trangles
-all angles< 90
define equilateral triangle
-equal sides
-equal angles
define right angled triangles
-1 angle is 90
define obtuse triangles
-1 angle is >90
angle in triangle
180
Exterior Angles Theorem
a + b + c= 180
x= a + b
c= 180 - x
-exterior angles is equal to sum of opp interior angles
define regular
all sides and angles equal
define bisect
cut exactly in half
formula of exterior angles of regular polygons
360 / n
n = no. sides
formula of interior angles of regular polygons
180 ( n -2 )
n = no. sides
define polygon
a shape with 3 or more straight sides
define concave polygons
a polygon with at least 1 interior angle over 180
-cannot be triangle
define convex polygons
polygon with all interior angles less than 180
is a circle a polygon
no
can a triangle be a concave polygon
no, concave polygons require 4 sides as one of the angles have to be above 180
properties of parallelogram
-diagonals bisect each other
-opp angles equal
-opp sides equal and parallel
properties of rectangle
-diagonals equal and bisect each other
-all angles 90
-opp sides equal and parallel
properties of square
-diagonals equal, bisect angles and each other at 90
-all angles 90
-all side equal
properties of rhombus
-diagonals bisect angles and each other at 90
-opp angles equal
-opp sides parallel
-all side equal
properties of trapezium
-1 pair of parallel sides
properties of kite
-diagonals bisect angles and intersect at 90
-1 pair of opp angles are equal
-2 pairs of equal adjacent sides
2 types of trapezium
-isos. trap.
-perpendicular trap.
relationship of rectangle and square
-square is a rectangle but rectangle is not a square
how to find sum of interior angles in a polygon
-from 1 point draw lines to other points inside the polygon
-180 x no. triangles found
polygon name with:
5, 6, 7, 8, 9, 10 sides
-pentagon
-hexagon
-heptagon
-octagon
-nonagon
-decagon
define circumference
perimeter of circle
define diameter
straight line from side to side of circle passing through center
define radius
straight line form 1 side of circle to center
define minor arc
arc less than 180
define major arc
arc more than 180
define minor sector
sector with central angle less than 180
define major sector
sector with central angle more than 180
define minor segment
part btw a chord and a minor arc
define major segment
part btw a chord and a major arc
define chord
straight line from side to side of circle without passing through center
