Chapter 3 Flashcards
What are corresponding angles?
They are equal to each other, on 2 parallel lines the angles in each equivalent place is equal. Eg
S=a
D=m etc.
S\ j --\---->----- D \c \ A\o -----\-->----- M \g
What are alternate angles?
On 2 parallel lines, angles on opposite lines and sides are equal eg
Angle d = angle a
----->---- \a \ D \ ----->---
What are interior angles?
When angles on 2 parallel lines add to make 180 eg
G+a=180
B+c=180
---------- G\b \ \ A \c ------------
What is this line called?
____________
\
\
The transversal
What do angles on s straight line add to?
180
What’s is congruency?
Shapes are congruent if they are exactly the same shape and size
What is SAS in congruent triangles?
SAS= side, angle, side (must be in that order)
What’s is ASA in congruent triangles?
ASA=angle,side,angle
What is AAS in congruent triangles?
AAS=angle, angle, side
What is SSS in congruent triangles?
SSS=side,side,side
What’s RHS in congruent triangles?
RHS= right angle, hypotenuse, side
What is the equation for the sun of interior angles of any polygon?
(N-2)x180
N=number of sides in polygon
What are the interior and exterior angles on a polygon?
they add to 180
A=interior
B=exterior
A+b=180
/-----\ /. \ /. \ \. / \. / \\_\_\_a_/_b\_\_\_\_
What do ALL the EXTERIOR angles in a polygon add to?
360
What is similarity?
They are the same shape(same angles) but different side lengths
What are similar shapes multiplied or divided by?
The linear scale factor
Same for both shapes when comparing similarity
What is the area scale factor?
Linear scale factor squared
What is the volume scale factor?
Linear scale factor cubed
What is the area scale factor equations?
Enlarged area=
Original area X linear scale factor
Original area=
Enlarged area divided by lsf^2
Lsf^2= enlarged area divided by original
What is the volume scale factor equations?
Enlarged area= original area X lsf^3
Original area= Enlarged area divided by lsf^3
Lsf^3= enlarged area divided by original
What is a bearing?
They are used to give a direction from a to b
Bearings are always measured:
- clockwise
- from a north line
- using 3 figures eg 26degrees is 026degrees
What is the difference of a bearing and reverse bearing?
180
Eg
Bearing. Reverse bearing
072. (+180 as below 180). 252
310 (-180 as bigger 180)130
:)