help???

Brandon uses the following steps to construct a perpendicular line through a point C on a line segments. He first draws two arcs from point C intersecting the line segment in point A and B. The next four steps are listed below.

1. Using the same compass width draw two more arcs from point C, one above and the other below the line.
2. Without changing the compass width draw two arcs from point B and below the line segment.
3. Label the point of intersection of the arcs above the line segment as M and below the line as N.
4. Using a straightedge, join point M and point N.

Question

help???


Brandon uses the following steps to construct a perpendicular line through a point C on a line segments. He first draws two arcs from point C intersecting the line segment in point A and B. The next four steps are listed below.

1. Using the same compass width draw two more arcs from point C, one above and the other below the line. 
2. Without changing the compass width draw two arcs from point B and below the line segment.
3. Label the point of intersection of the arcs above the line segment as M and below the line as N. 
4. Using a straightedge, join point M and point N.

anonymous · Answer

Part A: Which is the first incorrect step?
Part B: using complete sentences, explain your answer for part A.
Part C: Explain why a compass works for the construction done by Brandon.

anonymous · Answer

@Directrix 
@bohotness

anonymous · Answer

Step 1 --- the width of the compass must be increased 

step 2.) Arcs above from the left and right will only intersect at point C NOT above and below the line and will NOT make 2 points M and N if the width is not changed. 

 step 3.)The compass makes an arc of points that are equidistant from the pivot point. The perpendicular bisector of a line segment is a line composed of all points which are equidistant from the endpoints of the segment. The compass allows you to find 2 of those points, M and N. Any line is determined by 2 points, so the line drawn through M and N will contain all of those points and will be the perpendicular bisector. 

are these the answers?

fibonaccichick666 · Answer

I recommend drawing it out and labelling everything.  It ends up(if I read correctly) just using the wrong point.  Remember the idea behind this metod is that the angle bisector, altittude and perp bisector are all the same in an isoceles triangle

bohotness · Answer

i think a

anonymous · Answer

@ganeshie8 
@pooja195

mathmate · Answer

as suggested by @fibonacciChick666, the best way is to draw it according to the (wrong) instructions and you'll see the result, and hence the error.
Unless you're experienced in geometrical constructions (which is a rare gem these days, thanks to graphing calculators and software), it would be hard to spot the error.
Here are some hints below:
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