Brandon uses the following steps to construct a perpendicular line through a point C on a line segment. He first draws two arcs from point C intersecting the line segment in points A and B. The next four steps are listed below.
Step 1: Using the same compass width draw two more arcs from point C, one above and the other below the line.
Step 2: Without changing the compass width draw two arcs from point B above and below the line segment.
Step 3: Label the point of intersection of the arcs above the line segment as M and below the line as N.
Step 4: Using a straightedge, join point M and point N.
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.
Step 1: Using the same compass width draw two more arcs from point C, one above and the other below the line.
Step 2: Without changing the compass width draw two arcs from point B above and below the line segment.
Step 3: Label the point of intersection of the arcs above the line segment as M and below the line as N.
Step 4: Using a straightedge, join point M and point N.
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.
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The easiest way to answer the questions is to do the construction yourself. Either do it the wrong way Brandon did it and notice where he screwed up or do it the right way and notice how your way differs from Brandon.
Part C confuses me. It should be obvious from the question that a compass did not work for the construction done by Brandon. Perhaps your teacher meant "the construction attempted by Brandon".
Part C confuses me. It should be obvious from the question that a compass did not work for the construction done by Brandon. Perhaps your teacher meant "the construction attempted by Brandon".