(GEOMETRY HELP PLEASE!!) Describe the process to construct an acute scalene triangle with vertices PQR using only a compass and straightedge, where Q is a point on a horizontal line segment XY.

Question

anonymous · Answer

This is what I wrote, not sure if it's right:
You put the point of your compass on Point Q, change it to any width, and then draw an arc on the line segment XY. Next, without moving your compass out of the same place, you change the width and make another arc anywhere on the plane. Lastly, you put the compass point on the point where the arc would meet the line segment XY. Change the width and make the arc meet the second arc.

phi · Answer

that sounds like a scalene triangle, but it might be obtuse.

How about:  
You put the point of your compass on Point Q, change it to any width, and then draw an arc on the line segment XY.  Label the point where the arc meets XY as "R"

Next, without moving your compass out of the same place, you change the width **to make it a bit shorter** and make another arc 

 Lastly, you put the compass point on the point R.   Change the width ** to make it shorter again** (by a small amount)

 make the arc meet the second arc, and label the intersection P
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