Straight Line Graphs

1
Straight Line Graphs
y m x c
LO 11.2.1
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Straight Line Graphs

• y 2x 4

y
4
-2
0
x
Y 2 ( 0 ) 4 0 4
Y 2 ( -1) 4 - 2 4
Y 2(-2) 4 - 4 4
( -2 0)
3
Straight line graphs

• y m x c
• m is the gradient
• C is the y - intercept

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Straight line graphs y m x c
This graph cuts the y-axis at 5 Therefore c
5 The gradient is 5 down and 2 to the
left. ie -5 / -2 or m 5/2 The
equation is y 5/2 x 5 or 2y 5 x 10
5
5 down

• 2

2 across
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Straight line graphs y mx c

• Find the equation of this graph
• the y intercept is 3
• So c -3
• The gradient is
• 6 down and 3 to the left
• So m -6/-3 2
• Therefore the equation is
• y 2x 3

-3
6
Find the equation
4
The y intercept is 4 So c 4 The gradient is 6
down and 3 to the right OR 4 down and 2 to the
right. ie m - 4 / 2 -2
So equation is y - 2 x 4