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#26 2012-12-16 10:03:05

bob bundy
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Registered: 2010-06-20
Posts: 6,119

Re: Geometry review

Whoops!  Where did 'y' spring from ?  I hope you mean x + x - 35 = 90.

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#27 2012-12-16 10:20:23

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

Re: Geometry review

yup I mean x
So x is the large than the small angle is x-35

So x+x-35=90

x+x= 2x

-35+2x=90
-(-35)      -(-35)

2x=125

x = 62.5

So the measure of the larger angle is 62.5


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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#28 2012-12-16 10:33:25

bob bundy
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Posts: 6,119

Re: Geometry review

Yes.  In the question post (#23) you had 62.2  I assume a typo.

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#29 2012-12-16 13:11:27

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

Re: Geometry review

yeah its a typo


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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#30 2012-12-17 01:59:02

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

Re: Geometry review

I choose D because I didn't read the question correctly ammm but can I use the distance formula to get the answer ?


3. In the figure shown, line segment AC = CE  , D is the midpoint of  CE   , DE=5, and BC=2 . What is the measure of AB   ?

    A 5
    B7
    C8
    D10

View Image: clip_image011.gif

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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#31 2012-12-17 03:12:06

bob bundy
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Posts: 6,119

Re: Geometry review

hi zee-f

I've re-made the diagram with two extras:  (i) I've put on the given distances;  (ii) I've put a pointer to the midpoints.

You see, if AC = CE, then C is the midpoint of AE, and  D is the midpoint of CE.

So start with DE = 5, and work out CE.  From that answer work out AC.

Then use  BC = 2 to finish the problem.

Bob

View Image: zeef distance.gif

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#32 2012-12-17 04:10:16

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

Re: Geometry review

DE = 5 and I know that DE is half of CE So CE would equal CD*2 So CE=10

DE=5
CD=5
CE= 10
AC= 10
So AE= 20


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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#33 2012-12-17 04:13:05

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

Re: Geometry review

If I say the distance from B to c is 2
then AB would be 10-2=8


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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#34 2012-12-17 06:15:38

bob bundy
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Registered: 2010-06-20
Posts: 6,119

Re: Geometry review

Correct.  Well done.

Did you find my diagram helpful?

When I get one of your questions, the first thing I do is to make a diagram to show the problem.

Give it a try.

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#35 2012-12-17 06:48:34

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

Re: Geometry review

Yeah I sure did I drew it on my note book then found out how easy the question was smile I sure will try it next time big_smile

I corrected the following :
I choose D and it was incorrect
now I choose C

because adjacent angles are supplementary
AD = EH
FG=BC

So A= x
     b = 180 - x

So D is X F= 180-x

So the angles are supplementary because they add up to 180
4. Which statement about angle 1 and 2 must be true?

A  angle 1 is congruent to angle 2
B- 1 is the complement of  angle 2
C- angle 1 is the supplement of angle 2
D- Angle 1 and 2  are vertical angles

View Image: clip_image013.gif

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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#36 2012-12-17 06:51:51

bob bundy
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Registered: 2010-06-20
Posts: 6,119

Re: Geometry review

C is correct.

smile

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#37 2012-12-17 10:19:19

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

Re: Geometry review

I choose A and it was incorrect still confused dizzy


Ok so Obtuse Triangle has an angle that is  more than 90°  So that means only one angle is more than 90° and an isosceles triangle  has  two equal sides and two equal angles. So am thinking the last picture

5. Which triangle is an obtuse isosceles triangle?

View Image: clip_image017.gif View Image: clip_image018.gif View Image: clip_image019.gif View Image: clip_image020.gif

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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#38 2012-12-17 10:58:28

bob bundy
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Registered: 2010-06-20
Posts: 6,119

Re: Geometry review

Correct!

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#39 2012-12-17 22:52:24

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

Re: Geometry review

Ok first I choose B

My correction is :
area = (½)(apothem)(perimeter)

1/2 * 3.8 * 48 = 91.2

6. Calculate the area of the regular octagon shown.



A 21.9 square meters
B48.0 square meters
C91.2 square meters
D350.4 square meters

View Image: clip_image021.gif

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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#40 2012-12-17 22:55:28

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

Re: Geometry review

I need help solving this I choose D and it was incorrect

11. Which is the contrapositive of the following statement? If quadrilateral ABCD is a rectangle, then quadrilateral ABCD is a square.

A If quadrilateral ABCD is a square, then quadrilateral ABCD is a rectangle.
B If quadrilateral ABCD is not a square, then quadrilateral ABCD is not a rectangle.
C If quadrilateral ABCD is not a rectangle, then quadrilateral ABCD is not a square.
D If quadrilateral ABCD is not a square, then quadrilateral ABCD is a rectangle.


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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#41 2012-12-18 01:06:03

bob bundy
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Posts: 6,119

Re: Geometry review

hi zee-f

Q6.  91.2  That's what I get too.

Q11.  Structure for a contrapositive:

If <statement A>, then <statement B>   becomes if <NOT statement B>, then <NOT statement A>.

So both statements collect a NOT, and the order of statements is reversed.

The two versions are logically the same;  because if B is NOT true, then A cannot be either (as A true implies B true).

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#42 2012-12-18 02:26:46

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

Re: Geometry review

So A would be correct?


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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#43 2012-12-18 03:46:07

bob bundy
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Registered: 2010-06-20
Posts: 6,119

Re: Geometry review

A ?  Where are the NOTs ?

If <statement A>, then <statement B>   becomes if <NOT statement B>, then <NOT statement A>.

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#44 2012-12-18 05:43:28

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

Re: Geometry review

I thought you meant reverse the  statements

So B is the answer


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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#45 2012-12-18 05:46:59

bob bundy
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Registered: 2010-06-20
Posts: 6,119

Re: Geometry review

B is my answer too.  smile

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#46 2012-12-18 06:08:18

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

Re: Geometry review

8. Select which statement is true about the relationship between the measures of angle A and angle B in the diagram shown.

A The measure of angle A is greater than the measure of angle B   .
B The measure of angle B  is greater than the measure of angle A.
C The measure of angle A  is equal to the measure of angle B   .
D Cannot be determined without any other calculations.

#8- Ok so I first choose B but I still see that my answer is correct

because the measure of the missing angle would 2.38
Then I use cosine= A/H
9/11 = 0.82
cos-¹ = 34.92

So that is angle A
90+34.92=124.92
So angle B = 180 - 124.92 = 55.08

A= 34.92
B= 55.08
C= 90

View Image: clip_image023.gif

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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#47 2012-12-18 06:27:57

bob bundy
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Registered: 2010-06-20
Posts: 6,119

Re: Geometry review

Yes, that's ok.

My method was different but gets the same answer.

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#48 2012-12-18 07:42:48

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

Re: Geometry review

So what I did isn't incorrect right? but I answered B and it was incorrect


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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#49 2012-12-18 08:07:29

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

Re: Geometry review

I choose B and it was incorrect still cant find the answer neutral

16. A right circular cylinder has a base diameter of 12 meters and a height of 16 meters. What is the approximate total lateral surface area of the cylinder?   

A 602.9 m²
B 829.4 m²
C 1507.2 m²
D 2034.7 m²


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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#50 2012-12-18 08:51:44

bob bundy
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Registered: 2010-06-20
Posts: 6,119

Re: Geometry review

Q8. Sorry.  B is correct.  What I was trying to say is you could have got to the answer more quickly. 
But it doesn't matter.  Correct is correct however you get there.

Q16.  Not B.

You need to imagine the curved surface 'unwrapped' so that you have a rectangle.

height = 16  length = circumference of the circle = pi times D   area = height x circumference.

http://www.youtube.com/watch?v=gi7aaZ87EoQ

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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