Using a Protractor Practice

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Question 2

Use a protractor to measure ABC as shown in the picture below. Print out this page if you need to.

angle ABC greater than 180 degrees


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Select and check your answer...

A. 100°
B. 115°
C. 200°
D. 215°

Step by Step Solution

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    Step 1

    First, we can split the angle into two parts by drawing a dotted line along the line BC. Here, we know that we can get ABC by adding these two angles together.

    spliting the angle into 2 parts
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    Step 2

    Let's measure the first part. We place the protractor on the vertex B and make sure that its base line is along BC as shown:

    using the protractor to measure first angle
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    Step 3

    By reading the inner scale, we can see that this angle is 180°.

    this angle is 180 degrees
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    Step 4

    Next, we measure the second angle. We rotate the protractor and make sure that the base line is along AB as shown:

    measuring the second angle
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    Step 5

    By reading the outer scale, we can see that this angle is 45°.

    this angle is 45 degrees
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    Step 6

    Hence, we can get ABC by adding 180° with 45°.

    angle ABC is 225 degrees

    Clearly, the answer is D.