Perimeter of a Triangle Practice

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Question 1

Find the perimeter of a triangle that has the side lengths of 2cm, 6cm and 9cm.

Answer

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Select and check your answer...

A. 17 cm
B. 16 cm
C. 15 cm
D. 14 cm

Step by Step Solution

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    Step 1

    The picture below shows the triangle:

    a triangle with side lengths of 2cm, 6cm and 9cm
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    Step 2

    We start with the formula for the perimeter of a triangle, P, as shown below.

    formula for the perimeter of a triangle
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    Step 3

    Now, this formula simply means that we can find its perimeter by adding up all the side lengths together. Hence, we have:

    calculating the perimeter of a triangle
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    Step 4

    It is important to include the unit. Since, the sides lengths are given in cm, P will be in cm:

    P = 17cm
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    Step 5

    Therefore, the answer is A.

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