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#1 2012-11-22 14:09:19

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

area

I was wondering if my answer is correct

What is the area of this rectangle(in the img)?

A 17.06 sq units
B 60 sq units
C 21.6 sq units
D 53 sq units
E 28.9 sq units
F 51 sq units


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#2 2012-11-22 14:13:02

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: area

And I really need help with this :

18. What is the area of this polygon?

ls_XF    =    53 mm    ls_XV=    72 mm    ls_VR=    16 mm
ls_FB    =    31 mm    ls_BT    =    31 mm    ls_EU    =    47 mm
ls_UL    =    31 mm    ls_TL    =    88 mm    ls_DE=    16 mm
ls_RM=    70 mm    ls_MC=    21 mm    ls_DC=    70 mm



A- 8014 mm2
B- 7030 mm2
C- 6027 mm2
D- 5478 mm2
E- 1782 mm2
F- 1225 mm2


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#3 2012-11-22 20:24:59

Bob
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Registered: 2010-06-20
Posts: 10,056

Re: area

hi zee-f

For the first, I cannot see what answer you chose.

Did you work out the width first ?

For Q18, start by making a drawing on paper.  It doesn't have to be accurate, just make it look roughly like the given drawing.

Then mark on all the distances.

Split the shape into rectangles.  There's more than one way of doing this step.  I've shown one way on my diagram.

Using the length and width* for each rectangle, write down its area.

Add them up and you're done.

* You might have to do some adding or subtracting to work out the distances you need.

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#4 2012-11-22 23:16:07

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: area

I choose B for the first one and am working on #18


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#5 2012-11-23 01:19:06

Bob
Administrator
Registered: 2010-06-20
Posts: 10,056

Re: area

B is correct.

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#6 2012-11-23 08:27:59

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: area

but how do i get VE and FE?


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#7 2012-11-23 08:43:10

Bob
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Registered: 2010-06-20
Posts: 10,056

Re: area

Well it looks to me like RMCD is a rectangle, so RD = MC.

Then VE = VR + RD + DE

Or XVEF is a rectangle so VE = XF.

Try both ways and check they give the same answer.

And FE = XV

Or BE = TL - EU then FE = FB + BE

Hope that covers everything you need.

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#8 2012-11-24 07:36:31

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: area

ok So I got :

xvef= 3816

bult= 2728

RMCD= 1470

3816 + 2728 + 1470 = 8014 mm2


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#9 2012-11-24 08:11:58

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: area

20. What is the area of this polygon?

I got F


A 178 sq units
B 129 sq units
C 230 sq units
D 240 sq units
E 219 sq units
F 206 sq units


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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#10 2012-11-24 08:15:49

Bob
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Registered: 2010-06-20
Posts: 10,056

Re: area

hi

Q18 correct.  Well done!

Just give me a moment and I'll post again on the other one.

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#11 2012-11-24 08:18:47

Bob
Administrator
Registered: 2010-06-20
Posts: 10,056

Re: area

And also 206 is correct.  Excellent!

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#12 2012-11-24 08:21:32

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

Re: area

Thank you big_smile


One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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