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What is the measurement of DC? How do you know ?

What is the measurement of DC? How do you know ?-example-1
User Florian Berndl
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1 Answer

17 votes
17 votes

The vertices B, C and D form a right triangle.

Knowing 2 sides of the tright triangle, like BD and BC, we can find the length ofthe third side, DC, using the Pythagorean theorem: the sum of the squares of the length of the legs, DC and BC, is equal to the square of the length of the hypotenuse BD.


DC^2+BC^2=BD^2

Replacing with the values, we can calculate DC:


\begin{gathered} DC^2+60^2=100^2 \\ DC^2+3600=10000 \\ DC^2=10000-3600 \\ DC^2=6400 \\ DC=\sqrt[]{6400} \\ DC=80 \end{gathered}

Answer:

The correct options are

A: 80

B: Pythagorean theorem

User Actuallymicah
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2.8k points