Perpendicular Bisector of a triangle

AI Thread Summary
The discussion centers on the confusion regarding the perpendicular bisector of segment BC in a triangle and its intersection points with extended sides BA and CA. Participants clarify that the bisector intersects CA produced at point Q, which requires extending line CA. A revised diagram shows triangle PQC, where the length CP is given, and an angle measurement is provided to calculate PQ. However, the calculated value of PQ does not match the textbook answer, prompting questions about potential errors in the diagram or calculations. The conversation emphasizes the importance of accurately locating points P and Q based on the problem's description.
nmnna
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Homework Statement
##ABC## is a triangle such that ##\angle ABC = 37^{\circ}15'##, ##\angle ACB = 59^{\circ}40'##, ##BC = 8## cm; the perpendicular bisector of ##BC## cuts ##BA##, ##CA## produced at ##P, \ Q##. Find the length of ##PQ##.
Relevant Equations
##\tan(\alpha) = \frac{opposite \ side}{adjacent \ side}##
Here is my attempt to draw a diagram for this problem:
1617268604102.png

I'm confused about the "the perpendicular bisector of ##BC## cuts ##BA##, ##CA## produced at ##P, \ Q##" part of the problem.
How does perpendicular bisector of ##BC## cut the side ##CA##?
 
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It cuts CA produced. Extend the line CA until it meets the bisector. That point is Q (not where you have put it).
 
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mjc123 said:
It cuts CA produced. Extend the line CA until it meets the bisector. That point is Q (not where you have put it).
Thank you
 
mjc123 said:
It cuts CA produced. Extend the line CA until it meets the bisector. That point is Q (not where you have put it).
1617290558617.png

I changed my diagram.
Now I have the right triangle ##\triangle PQC##, where ##CP = 4##cm (since ##PQ## is a perpendicular bisector), ##\angle QCP = 59^{\circ}40'##, so I can find ##PQ## using the relation $$\tan\angle QCP = \frac{PQ}{CP}$$
I got ##\approx 6.818## which is not the answer given in my textbook. Where did I go wrong?
 
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nmnna said:
View attachment 280723
I changed my diagram.
Now I have the right triangle ##\triangle PQC##, where ##CP = 4##cm (since ##PQ## is a perpendicular bisector), ##\angle QCP = 59^{\circ}40'##, so I can find ##PQ## using the relation $$\tan\angle QCP = \frac{PQ}{CP}$$
I got ##\approx 6.818## which is not the answer given in my textbook. Where did I go wrong?
The description seems confusing to me as well.
Could it be that point P should be located where the perpendicular bisector of BC cuts BA?
What is the answer given in your textbook?
If it is close to 3.75 cm, then your last diagram is not correct regarding location of P.
 
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P is the point you have called L. The original statement, which is perhaps not as clear as it might be, means "the perpendicular bisector of BC cuts BA at P and cuts CA produced at Q."
 
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mjc123 said:
P is the point you have called L. The original statement, which is perhaps not as clear as it might be, means "the perpendicular bisector of BC cuts BA at P and cuts CA produced at Q."
Thank you for your help.
 
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