equation of a line
DESCRIPTION
Equation of a straight lineTRANSCRIPT
EQUATIONS OF STRAIGHT LINES
AIM: UNDERSTAND THE GRADIENT AND INTERCEPT OF A STRAIGHT LINE AND EQUATIONS OF THE FORM y=mx + c
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Intercept is 1
1 across
2 up
The gradient is 2 because the line slopes upwards 2 for every one square across
The equation of the line isy = 2x + 1
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4 up
2 across
What is the gradient now?
The gradient is still 2
Intercept is 1
The equation of the line isy = 2x + 1
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4 up
1 across
The gradient is 4 because the line slopes upwards 4 for every one square across
Intercept is 3
The equation of the line isy = 4x + 3
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3 up
1 across
The gradient is 3 because the line slopes upwards 3 for every one square across
Intercept is 2
The equation of the line isy = 3x + 2
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1 up
2 across
The gradient is ½ because the line slopes upwards ½ for every one square across
Intercept is 5
The equation of the line isy = ½ x + 5
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2 up
3 across
The gradient is ⅔ because the line slopes upwards ⅔ for every one square across
The equation of the line isy = ⅔ x + 6
Intercept is 6
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2 down
1 across
The gradient is -2 because the line slopes downwards 2 for every one square across
Intercept is10
The equation of the line isy = -2 x + 10
ory= 10 – 2x
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4 5 6
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1
1
2
2 3
3
4
4 5 6
5
6
7
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9
10
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1
1
2
2 3
3
4
4 5 6
5
6
7
8
9
10
11
12