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What needs to be corrected in the following construction for copying ABC with point D as the vertex?

-The second arc should be drawn centered at K through A.
-The second arc should be drawn centered at J through A.
-The third arc should cross the second arc.
-The third arc should pass through D.

What needs to be corrected in the following construction for copying ABC with point-example-1
User Salyh
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2 Answers

2 votes

Answer:

Explanation:

User Philwills
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2 votes

Answer:

(c) The third arc should cross the second arc.

Explanation:

You want to know the correction required to the construction of a copy of an angle.

Copying an angle

To copy an angle to a new vertex, arcs are drawn with the same radius at the original vertex (first arc) and the new vertex (second arc).

Then the compass is set to the length JK, and a third arc is drawn with L as the center, marking off the distance JK on the second arc.

In order do that, the third arc should cross the second arc.

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Additional comment

This allows you to create ∆DLM congruent to ∆BKJ. Hence angle D will be congruent to angle B.

It helps to actually do these constructions on paper using compass and straightedge. That gives you better intuition about how they work, and about geometric relations in general.

User Kisha
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