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Maths help - urgent!

The triangle PQR has vertices P(8,6), Q(0,2), and R(2,r). Find the values of r when the triangle is isosceles with RQ=RP
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Anonymous #1
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anyoneeee please?
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Notnek
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Original post by Anonymous
anyoneeee please?

Are you aware that there's a Maths forum for posting maths questions?
Hopefully this makes sense...Plot P and Q and draw a straight line from P to Q. Measure halfway along this line and draw a dashed line at a 90 degree angle to the PQ line.Also draw a vertical dashed line straight upwards from (2,0)Where the two dashed lines meet is where R needs to be. I think it's (2,9) but that is just from a rough drawing!
Original post by Anonymous
The triangle PQR has vertices P(8,6), Q(0,2), and R(2,r). Find the values of r when the triangle is isosceles with RQ=RP

Write expressions for the vectors RQ and RP. Hint: AB = B - A.

Now write the magnitude of each of those, and equate them. Solve for r.
Original post by RogerOxon
Write expressions for the vectors RQ and RP. Hint: AB = B - A.

Now write the magnitude of each of those, and equate them. Solve for r.

I did this quickly, so I may have made a mistake, but I get one value for r, which is between 7 and 10.

If you have issues, please post what you get for the vectors RQ and RP, and their magnitudes.
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Anonymous #1
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thank you!

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