Question 127270:  Graph the quadratic equation after completing the given table of values.    
 y = x^2 – 1 
 
x	     y 
–2	 
–1	 
 0	 
 1	 
 2	 
Please assist me with this question, as I am lost. 
Thanks
 
 
 Found 2 solutions by  checkley71, jim_thompson5910: Answer by checkley71(8403)      (Show Source):  Answer by jim_thompson5910(35256)      (Show Source): 
You can  put this solution on YOUR website! In order to graph  , we need to plot some points. To do that, we need to plug in some x values to get some y values
 
 
 
So let's find the first point:
 
 
 
 
  Start with the given function
 
 
 
  Plug in  
 
 
 
  Raise -2 to the 2nd power to get 4
 
 
 
  Multiply 1 and 4 to get 4
 
 
 
  Subtract 1 from 4 to get 3
 
 
 
So when  , we have  
 
 
 
So our 1st point is (-2,3)
 
 
 
--------------  Let's find another point  --------------
 
 
 
  Start with the given function
 
 
 
  Plug in  
 
 
 
  Raise -1 to the 2nd power to get 1
 
 
 
  Multiply 1 and 1 to get 1
 
 
 
  Subtract 1 from 1 to get 0
 
 
 
So when  , we have  
 
 
 
So our 2nd point is (-1,0)
 
 
 
--------------  Let's find another point  --------------
 
 
 
  Start with the given function
 
 
 
  Plug in  
 
 
 
  Raise 0 to the 2nd power to get 0
 
 
 
  Multiply 1 and 0 to get 0
 
 
 
  Subtract 1 from 0 to get -1
 
 
 
So when  , we have  
 
 
 
So our 3rd point is (0,-1)
 
 
 
--------------  Let's find another point  --------------
 
 
 
  Start with the given function
 
 
 
  Plug in  
 
 
 
  Raise 1 to the 2nd power to get 1
 
 
 
  Multiply 1 and 1 to get 1
 
 
 
  Subtract 1 from 1 to get 0
 
 
 
So when  , we have  
 
 
 
So our 4th point is (1,0)
 
 
 
--------------  Let's find another point  --------------
 
 
 
  Start with the given function
 
 
 
  Plug in  
 
 
 
  Raise 2 to the 2nd power to get 4
 
 
 
  Multiply 1 and 4 to get 4
 
 
 
  Subtract 1 from 4 to get 3
 
 
 
So when  , we have  
 
 
 
So our 5th point is (2,3)
 
 
 
Now lets make a table of the values we have calculated
 
 
Now plot the points
 
 
 
 
 
Now connect the points to graph    (note: the more points you plot, the easier it is to draw the graph)
 
  
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