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Maths year 11

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Original post by z_o_e
1 interior angle is - 1080/8 =135

So 135 +2y=360?

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Yes. I hope it makes sense why and where everything comes from.
Reply 481
Original post by B_9710
No they're not wrong. You have correctly calculated that one of the interior angles is 135 degrees. You can then halve it, which gives you the angle PAB and then the angles PAB and EAB are supplementary - thy add to 180 degrees as they're on a straight line.


I got this

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Reply 482
Original post by RDKGames
Yes. I hope it makes sense why and where everything comes from.


Is the answer correct? It's above xx

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Original post by z_o_e
Is the answer correct? It's above xx

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Yes it is. :smile:
Reply 484
Original post by RDKGames
Yes it is. :smile:


Thank you xx

For this do I find the interior angle of both of the shapes and then add them up and subtract 360 by the total and I would get X?

Or does it have something to do with the straight lines adding up to 180?

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Original post by z_o_e
Thank you xx

For this do I find the interior angle of both of the shapes and then add them up and subtract 360 by the total and I would get X?

Or does it have something to do with the straight lines adding up to 180?

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Either method will work, I personally just find summing up the angles to 360 more straight forward. If a is the interior angle of the hexagon and b is the interior angle of the octagon, then it makes sense that 360=a+b+x as they make up the circle centered around that vertex.
Reply 486
Original post by RDKGames
Either method will work, I personally just find summing up the angles to 360 more straight forward. If a is the interior angle of the hexagon and b is the interior angle of the octagon, then it makes sense that 360=a+b+x as they make up the circle centered around that vertex.


Is this correct?



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Your interior angle for the octagon is incorrect. You got 8-2=6 yet you used a 7.

Otherwise your working is correct.


Interior angle of an octagon is 135 degrees.
Reply 490
Original post by RDKGames
Your interior angle for the octagon is incorrect. You got 8-2=6 yet you used a 7.

Otherwise your working is correct.


Thank you xxx

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Reply 491
Original post by B_9710
Interior angle of an octagon is 135 degrees.




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Reply 494
Original post by RDKGames
Correct.


This is a bit harder.

What steps would I need to use? And methods.

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Original post by z_o_e
This is a bit harder.

What steps would I need to use? And methods.

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Simple. Work out the overall area; which is simple the whole rectangle and I'm sure you know how to work that out; let's call this area A.

Next work out the area of the patio which is again just finding the area of the rectangle; lets call this area P.

Now to work out the area of the two ponds, remember that the area of a circle is πr2\pi r^2 and the radius is half the diameter (you can use π=3.14\pi=3.14 if you're calculator doesn't have it). Once you have the area of one pond, multiply it by 2 because there are two ponds which should give you the total area that the 2 ponds take; call this area R.

Now the area of the grass, G, it would be G=A-P-R (Total area take away the patio and take away the two ponds)

Once you have the grass area, you can work out how many boxes are needed.
(edited 7 years ago)
Reply 496
Original post by RDKGames
Simple. Work out the overall area; which is simple the whole rectangle and I'm sure you know how to work that out; let's call this area A.

Next work out the area of the patio which is again just finding the area of the rectangle; lets call this area P.

Now to work out the area of the two ponds, remember that the area of a circle is πr2\pi r^2 and the radius is half the diameter (you can use π=3.14\pi=3.14 if you're calculator doesn't have it). Once you have the area of one pond, multiply it by 2 because there are two ponds which should give you the total area that the 2 ponds take; call this area R.

Now the area of the grass, G, it would be G=A-P-R (Total area take away the patio and take away the two ponds)

Once you have the grass area, you can work out how many boxes are needed.


So I work out area of grass and patio separately and add it up to find the sum of the whole area?

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Original post by z_o_e
So I work out area of grass and patio separately and add it up to find the sum of the whole area?

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You get the area of the grass differently than others. When you do 17x9.5 you are finding the whole area, which includes the patio, the grass and the 2 ponds. You don't want the ponds and the patio so you take their areas away which only leaves the area of the grass.
Reply 498
Original post by RDKGames
You get the area of the grass differently than others. When you do 17x9.5 you are finding the whole area, which includes the patio, the grass and the 2 ponds. You don't want the ponds and the patio so you take their areas away which only leaves the area of the grass.




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Pond + pond + patio is wrong. Work them out individually and add them up.

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