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# D1 Ocr Help watch

1. The answer in the mark scheme is driving me nuts!1 I just dont understand how they got the feasible region with those equations.

This is the link to the mark scheme and if you search the code 4736 to find D1

Question no. 5(v)

how does the line x+y=22 and x+3y=45 crosses at those points man.
HELP PLOX
im going crazy
2. is this MEI d1?
3. (Original post by tomdebs)
is this MEI d1?
Nope just normal OCR D1
4. sorry,i dont know how much of the question you dont understand so tell me if this helps.
to eliminate Z the equations are rewritten by substituting 24-x-y for Z.
therefore Z>=2 becomes 24-x-y>=2 which gives x+y<=22.
and 4x+2y+5z<=75 becomes 4x+2y+(120-5x-5y)<=75 which gives x+3y>=45
then find the intercepts of the equations shade and identify the feasible region.
hope this helps.
and ur origin should be 9 instead of 0 .
5. (Original post by tomdebs)
sorry,i dont know how much of the question you dont understand so tell me if this helps.
to eliminate Z the equations are rewritten by substituting 24-x-y for Z.
therefore Z>=2 becomes 24-x-y>=2 which gives x+y<=22.
and 4x+2y+5z<=75 becomes 4x+2y+(120-5x-5y)<=75 which gives x+3y>=45
then find the intercepts of the equations shade and identify the feasible region.
hope this helps.
and ur origin should be 9 instead of 0 .
Thanks but i understand that part. I just dont get how they got the graph with cross the y-axis at those points shown in the mark scheme. Surely the line x+y=22 will cross the axis at (0,22) and (22,0)? But the question asks to show the values from 9 to 15.

Im really confused
6. (Original post by Concretepoo)
Thanks but i understand that part. I just dont get how they got the graph with cross the y-axis at those points shown in the mark scheme. Surely the line x+y=22 will cross the axis at (0,22) and (22,0)? But the question asks to show the values from 9 to 15.

Im really confused
then use the intercepts of when y=9 and x=9
because like i mentioned before ur origin is 9 and ur highest value is 15 for both x and y.it like a rescaled graph.
hope this helps.
7. (Original post by tomdebs)
then use the intercepts of when y=9 and x=9
because like i mentioned before ur origin is 9 and ur highest value is 15 for both x and y.it like a rescaled graph.
hope this helps.
OMFG IM SO DUMMB !!
Thanks man!
8. Hi
Does anyone have the June 2009 paper?

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