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| Question 206056:  How do you turn this inequality into an equation you can graph 9x-2y<-18?
 Found 2 solutions by  RAY100, stanbon:
 Answer by RAY100(1637)
      (Show Source): 
You can put this solution on YOUR website! Let's  make  a  base  line by  assuming  9x-2y = -18 .
 The  T  box  might  look  like
 .
 x,,,,,,,,,,,,y
 .
 0,,,,,,,,,,,,9,,,,,,,-2y=-18
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 -2,,,,,,,,,,,0,,,,,,,,9x= -18
 .
 2,,,,,,,,,,,18,,,,,,,,9x-36 =-18
 .
 Now,  plot  these  using  a  dashed  line,  no  equal  sign,
 .
 Now,  ,lets  pick  which  side  of  the  line  of  the  "area  of  concern.
 .
 The  test  point  might  be  (0,0),,,below  the  line,,,,,
 our  eqn  becomes, 9(0)-2(0) < -18,,or  0<-18,  which  is  NOT TRUE,,,,
 therefore  our  answer  is  above  the  line.
 .
 To  verify,  lets pick  a  point  above  the  line,  (0,10) and  see  if  the  eqn is  valid,,,,,,9(0) -2(10) < -18,,,,-20<-18,,,ok,  so  area  is  above  line.
 .
 Usually  we  shade  this  area  by  cross  hatching.
 
 
 
Answer by stanbon(75887)
      (Show Source): 
You can put this solution on YOUR website! How do you turn this inequality into an equation you can graph 9x-2y<-18? ---------------------
 You graph the boundary of the inequality, which is the equality.
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 Solve the inequality for "y":
 2y < 9x + 18
 y < (9/2)x + 2
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 Graph the boundary which is y = (9/2)x + 2
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 Now look at the inequality.
 Since you want y to be LESS than the boundary,
 shade the half-plane BELOW the boundary.
 That shaded half-plane is the graph of the inequality.
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 Cheers,
 Stan H.
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