Graph Questions

Parts of a Graph

​Y-intercept

• The y-intercept is where the graph hits the y-axis.
  
• In a word problem, this is the starting amount.
  
• In a word problem, we have zero x things at the y-intercept.
  
• x=0 at the y-intercept.
  

X-intercept/Roots/Zeros/Solutions

• All four of those names mean exactly the same thing.  The x-intercept is where the graph hits the x axis.
  
• y=0 at the x-intercept.
• In a word problem, we have zero y things at the x-intercept.

Slope

• Slope is our Rate Of Change.
  
• Slope is how fast our line goes up or down.
  
• In a word problem, it has the words:  Rate Of Change, Per, or Each next to it.
  
•   

Correlation

• Correlation tells us about the strength and direction of the relationship between the x things and the y things.  
  
• When correlation is positive, that means as the x things get bigger, so do the y things.
  
• When correlation is negative, that means when the x things are getting bigger, the y things are getting smaller.
  
• Positive Strong.  Looks like a line and it is going up.
  

• Negative Strong.  Looks like a line and it is going down.
  

• Positive Weak.  Looks more blobby, but it is going up.
  

• Negative Weak.  Looks more blobby, but it is going down.
  

• No Correlation.  Looks like a bunch of random dots everywhere.  No obvious pattern.
  

Prediction

• These usually ask,"When the x things are _____, what would you expect the y things to be?"
  
• First step, circle the dots.  We want our answer to be inside the circle.
  

• Then go to where the x things equals what they are asking about.  Draw a line up to the middle of the circle.  Then draw a line left to the y axis to see what they y things are there.
  

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Mr. Lake's Math Site