Find the area of the quadrilateral

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Homework Help Overview

The discussion revolves around finding the area of a quadrilateral given certain dimensions, with participants exploring the feasibility of calculating the area based on the provided information. The problem involves geometric concepts and properties related to triangles and quadrilaterals.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • Participants discuss the implications of missing dimensions and the positioning of point D. There are considerations of using trigonometric functions and properties of triangles, alongside questioning the assumptions regarding angles in the quadrilateral.

Discussion Status

Several participants express uncertainty about the ability to determine the area due to insufficient information. Some suggest that the area could vary based on the location of point D, while others reflect on the geometric properties that may or may not apply. There is an acknowledgment of the limitations in the current approach, and some participants indicate a willingness to revisit the problem later.

Contextual Notes

Participants note that the area of triangle ACD cannot be determined without knowing the lengths of certain sides, which directly affects the ability to find the area of the quadrilateral ABCD. There is also mention of the cyclic nature of angles in quadrilaterals, which adds complexity to the problem.

chwala
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Homework Statement
See attached
Relevant Equations
sine rule
I was looking at this problem today, and i was trying to figure out its area with the given dimensions shown. First, is this even possible?...i later looked at the problem in detail and realized that i had missed out on some dimension that was given on the text.
Having said that, i would like to try and see if its possible to find the area of the quadrilateral with the given dimensions as indicated...i would nevertheless like to know whether this is possible. I will try look at it and share my working later...i will make use of sine, cosine rule and the angle property of parallelogram...

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There is not enough to determine where point ##D## is. The area of triangle ##ACD## could be anything.
 
PeroK said:
There is not enough to determine where point ##D## is. The area of triangle ##ACD## could be anything.
I was thinking of angle ##B##+##D##=##180^0##... this has to fix the point ##D## at some point...
 
chwala said:
I was thinking of angle ##B##+##D##=##180^0##... this has to fix the point ##D## at some point...
You can put D wherever you like. BCD is any triangle with a base of 5m.
 
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chwala said:
I was thinking of angle ##B##+##D##=##180^0##... this has to fix the point ##D## at some point...
Angles B and D would only add to 180 degrees for a cyclic quadrilateral.
 
Let me try and crack this tomorrow...sorry i have been a bit busy with work...let's see where i reach on this...i will try and find the dimensions of the quadrilateral...of course by use of the parallelogram property...then i may agree with you if its impossible...thanks Perok and Steve4Physics man!:cool:
 
Steve4Physics said:
Angles B and D would only add to 180 degrees for a cyclic quadrilateral.
Aaargh that's true...i overlooked that! let's see how far I go with this...
 
@chwala, what part of @PeroK's point escaped you? You don't need trig functions and such for this; it's 5th grade geometry:

##\mathrm{area~of}~\triangle = \frac 12(\mathrm{base}\times\mathrm{height})##.

In the illustration, increasing the lengths of CD and AD would increase the height. Since we don't know those lengths, we can't find the area of triangle ACD, and without knowing that area, we can't know the area of quadrilateral ABCD.
 
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sysprog said:
@chwala, what part of @PeroK's point escaped you? You don't need trig functions and such for this; it's 5th grade geometry:

##\mathrm{area~of}~\triangle = \frac 12(\mathrm{base}\times\mathrm{height})##.

In the illustration, increasing the lengths of CD and AD would increase the height. Since we don't know those lengths, we can't find the area of triangle ACD, and without knowing that area, we can't know the area of quadrilateral ABCD.
True, it's not possible to find the area...I just tried looking at it...cheers mate...
 
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