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I'm an IGCSE Maths Teacher - Post your questions here.

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inquisitiveness

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yes its not on the boundary line that was my confusion,we always take points that are only in the boundary line(if solid lines are there)right?and never include ones in the center that are not on boundary.....?and if there was a dashed line then the ones on boundary would not be included for example point 7,6 as this is not included in equality so we would take the ones in center like 9,5?
 
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notnek01

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inquisitiveness said:
yes its not on the boundary line that was my confusion,we always take points that are only in the boundary line(if solid lines are there)right?and never include ones in the center that are not on boundary.....?and if there was a dashed line then the ones on boundary would not be included for example point 7,6 as this is not included in equality so we would take the ones in center like 9,5?
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I think you're a bit confused here.

The points in the centre of the boundary are always part of the solution. The boundary points are only included in the solution if the boundary line is solid.

You have to read the question to work out which point to choose. There could be a question where you need to choose a point in the centre or a question where you need to choose a point on the boundary (this is more common).
 
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inquisitiveness

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notnek01 said:
I think you're a bit confused here.

The points in the centre of the boundary are always part of the solution. The boundary points are only included in the solution if the boundary line is solid.

You have to read the question to work out which point to choose. There could be a question where you need to choose a point in the centre or a question where you need to choose a point on the boundary (this is more common).
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so the question that would require me to choose points from center and NOT from boundary line is when the inequality is a dashed line and the question that would require me to try all points on center plus the ones on boundary is when the inequality is equal to or greater than(solid line) right?or is there something else i need to consider in order to determine if i shou;d take points on center plus boundary or just bondary lines?
 
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notnek01

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inquisitiveness said:
so the question that would require me to choose points from center and NOT from boundary line is when the inequality is a dashed line and the question that would require me to try all points on center plus the ones on boundary is when the inequality is equal to or greater than(solid line) right?or is there something else i need to consider in order to determine if i shou;d take points on center plus boundary or just bondary lines?
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This is still not right. Maybe you're getting confused with my term, 'solution region'.

The solution region contains any point that satisfies the inequalities.

The centre points are always included in the solution region. It doesn't matter if the boundary lines are dashed or solid.

Only solid boundary lines are included in the solution region. Dashed lines are not included.

In your diagram, there are 16 whole number solutions in the solution region. You should have dots in the centre as well as on the boundary line.

Now a question might say something like, 'Find the solution that gives ______' or 'Find the least possible ______'. For this, you need to choose a point in the solution region which could be in the centre or on the boundary (normally the boundary).
 
I

inquisitiveness

Messages
105
Reaction score
9
Points
28
notnek01 said:
This is still not right. Maybe you're getting confused with my term, 'solution region'.

The solution region contains any point that satisfies the inequalities.

The centre points are always included in the solution region. It doesn't matter if the boundary lines are dashed or solid.

Only solid boundary lines are included in the solution region. Dashed lines are not included.

In your diagram, there are 16 whole number solutions in the solution region. You should have dots in the centre as well as on the boundary line.

Now a question might say something like, 'Find the solution that gives ______' or 'Find the least possible ______'. For this, you need to choose a point in the solution region which could be in the centre or on the boundary (normally the boundary).
Click to expand...
ohhhhhhhhhhhhh thank youuuuuuuuu
 
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