What is the angle needed to solve this right triangle?

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Homework Help Overview

The discussion revolves around solving a right triangle problem involving angles and side lengths. The original poster attempts to determine the angle needed to complete the triangle, while also addressing a potential discrepancy in the given angles.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the calculations made by the original poster regarding the lengths of sides based on tangent ratios. Questions arise about the accuracy of the angles provided and whether there is a typo in the problem statement. Some participants suggest clarifications regarding the angles involved.

Discussion Status

The discussion is ongoing, with some participants providing hints and suggestions for finding the required angle. There is recognition of a possible typo, but no consensus has been reached regarding the correctness of the original poster's solution.

Contextual Notes

Participants note the potential for a typo in the problem statement regarding the angles, which may affect the calculations. The original poster expresses uncertainty about the angle needed and seeks further guidance.

nmnna
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Homework Statement
In figure ##\angle{ABC} = 90^\circ = \angle{BCD}, \ \angle{ACB} = 41.45^\circ, \ \angle{CBD} = 32.73^\circ, \ BC = 10##cm. Calculate ##AB, \ CD## and ##\angle{AEB}##
Relevant Equations
##\tan{\alpha} = \frac{opposite \ side}{adjacent \ side}##
The Figure
1616228240588.png

My Attempt at Solution

##\tan{ACB} = \frac{AB}{BC}, \ \tan41.45^\circ = \frac{AB}{10} \Rightarrow AB = 10\tan45.41^\circ \approx 8.83##cm
Similarly
##\tan{CBD} = \frac{CD}{BC}, \ \tan32.73^\circ = \frac{CD}{10} \Rightarrow CD = 10\tan32.73^\circ \approx 6.43##cm
After this I checked the answer in my textbook, and instead of 6.43cm the answer for ##CD## was 4.40cm.
I thought that there was a typo in the problem, so instead of ##32.73^\circ##, I tried ##23.73^\circ##, and surprisingly the answer matches with the one in the textbook.
So I'd like to know if it really is a typo or my solution is wrong.
And I can't find the angle required in the problem, so I'd be grateful if you give me some hints for finding this angle.
 
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nmnna said:
Homework Statement:: In figure ##\angle{ABC} = 90^\circ = \angle{BCD}, \ \angle{BCD} = 41.45^\circ,
You have angle ##BCD## twice there. Please clarify.
 
PeroK said:
You have angle ##BCD## twice there. Please clarify.
It should be ##ACB##
 
nmnna said:
So I'd like to know if it really is a typo or my solution is wrong.
And I can't find the angle required in the problem, so I'd be grateful if you give me some hints for finding this angle.
Looks like a typo.

A hint to find the angle ##AEB##. First extend the line ##AB## to a new point, ##F##, so that ##AFD## is a right angle. Then you have another angle equal to ##AEB##.
 
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Your work is correct starting with the numbers you were given.
 
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