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#1 Help Me ! » Geometry Help » 2017-04-09 09:46:05
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- Replies: 2
In triangle $ABC$, $\angle A = 36^\circ$ and $\angle B = \angle C = 72^\circ$. Let $\overline{BD}$ be the angle bisector of $\angle ABC$.
(a) Prove that $BC = BD = AD$.
(b) Let $x = BC$ and let $y = CD$. Using similar triangles $ABC$ and $BCD$, write an equation relating $x$ and $y$.
(c) Write the equation from Part b in terms of $r=\frac yx$ and find $r.$
(d) Compute $\cos 36^\circ$ and $\cos 72^\circ$ using Parts a-c. (Do not use your calculator!)
#2 Re: Help Me ! » Geometry Help! » 2017-04-09 09:45:05
Never mind, i got the correct answer. it is 18
#3 Re: Help Me ! » Geometry Help! » 2017-04-08 07:32:11
Should I use the sine rule for Q3?
#4 Re: Help Me ! » Geometry Help! » 2017-04-08 06:13:50
Can somebody give me some help on Q3? Thanks!
#5 Help Me ! » Help Please » 2017-03-27 10:36:31
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- Replies: 1
When plotted in the standard rectangular coordinate system, trapezoid $ABCD$ has vertices $A(1, -2)$, $B(1, 1)$, $C(5, 7)$ and $D(5, 1)$. What is the area of trapezoid $ABCD$?
#6 Re: Help Me ! » Help Please » 2017-03-27 10:00:08
I got six for my answer. It's correct. Thanks!
#7 Help Me ! » Help Please » 2017-03-26 11:44:29
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- Replies: 3
What is the area in square units of the convex quadrilateral with vertices $(-1, 0)$, $(0, 1)$, $(2, 0)$ and $(0, -3)$?
#8 Help Me ! » Geo help » 2017-03-24 09:46:46
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- Replies: 3
The lines y =5/12 x and y =4/3x are drawn in the coordinate plane. Find the slope of the line that bisects the angle between these lines.
#9 Help Me ! » Geo help please » 2017-03-24 08:35:07
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- Replies: 1
In triangle
, , is the midpoint of , is the foot of the perpendicular from to , and is the midpoint of . Prove that is perpendicular to .#10 Help Me ! » Transformations Help » 2017-03-11 10:45:28
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- Replies: 1
Let ABCD be a square of side length 1. Let P be a point on side CD such that angle DAP = 20. Let Q be a point on side
BC such that angle BAQ = 2. Find the perimeter of triangle CPQ.
#11 Re: Help Me ! » 3D Geometry Help Please » 2017-03-06 14:03:40
I'm unsure of how to approach this. Should i plug in numbers and do trial and error? I don't know.
#12 Re: Help Me ! » 3D Geometry Help Please » 2017-03-06 12:28:41
Could you guys give me some help on this problem?
#13 Re: Help Me ! » 3D Geometry Help Please » 2017-02-22 11:39:18
Yeah disregard any wastage
#14 Help Me ! » 3D Geometry Help Please » 2017-02-21 11:13:43
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- Replies: 8
Lisa, a child with strange requirements for her projects, is making a rectangular cardboard box with square bases. She wants the height of the box to be 3 units greater than the side of the square bases. What should the height be if she wants the surface area of the box to be at least 90 square units while using the least amount of cardboard?
#15 Re: Help Me ! » Geometry Help Please » 2017-02-21 11:05:08
I got the correct answer! Thanks bob bundy!
#16 Help Me ! » Geometry Help Please » 2017-02-17 15:04:34
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- Replies: 4
To be able to walk to the center C of a circular fountain, a repair crew places a 16-foot plank from A to B and then a 10-foot plank from D to C, where D is the midpoint of Line AB . What is the area of the circular base of the fountain? Express your answer in terms of pi.
Help is greatly appreciated!
#17 Re: Help Me ! » DIFFICULT (for me) GEO PROBLEMS » 2017-02-03 10:58:37
Could you help me with q3?
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