Difference between revisions of "Proportional"
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: On a [[proportional]] [[Scatter Graph|scatter graph]] when one [[variable]] increases, the other increase or when one increases the other decreases. | : On a [[proportional]] [[Scatter Graph|scatter graph]] when one [[variable]] increases, the other increase or when one increases the other decreases. | ||
: A [[proportional]] graph may have a non-zero [[y-intercept]]. | : A [[proportional]] graph may have a non-zero [[y-intercept]]. | ||
| − | + | : If the [[Line of Best Fit|line of best fit]] has a [[y-intercept]] of zero then it is called '[[Directly Proportional|directly '''proportional''']]'. | |
===Examples=== | ===Examples=== | ||
{| class="wikitable" | {| class="wikitable" | ||
Revision as of 10:30, 25 March 2019
Key Stage 4
Meaning
When two variables are proportional they change together by a constant amount.
About Proportional Graphs
- A scatter graph showing a proportional relationship has a linear gradient.
- On a proportional scatter graph when one variable increases, the other increase or when one increases the other decreases.
- A proportional graph may have a non-zero y-intercept.
- If the line of best fit has a y-intercept of zero then it is called 'directly proportional'.
Examples
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| This scatter graph shows a linear relationship that is proportional where x increases, y increases.
\(y = mx + c\) Where m, the gradient, is positive. |
This scatter graph shows a linear relationship that is proportional where x increases, y decreases.
\(y = mx + c\) Where m, the gradient, is negative. |
This scatter graph shows a linear relationship that is directly proportional where x doubles, y doubles.
\(y = mx\) Where m, the gradient, is positive. |