Analysis and Approaches for IBDP Maths Ebook 1 | Page 87

Front Page
Chapter
9
Equations of Straight
SUMMARY POINTs
Lines
9
� Consider the points P( x1, y
1)
and Q( x2, y
2)
on a x - y plane:
y � y
m � : Slope of PQ
x � x
1.
2 1
2.
2 1
d � ( x � x ) � ( y � y ) : Distance between P and Q
3.
1 2 1 2
2 2
2 1 2 1
� x � x ,
y �
�
y
� 2 2
�
�: The mid-point of PQ
�
� Forms of straight lines with slope m and y -intercept c :
1. y �mx � c : Slope-intercept form
2. Ax � By �C
� 0 : General form
�
Ways to find the x -intercept and the y -intercept of a line:
1. Substitute y � 0 and make x the subject to find the x -intercept
2. Substitute x � 0 and make y the subject to find the y -intercept
Solutions of Chapter 9
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