Answer: Choice B
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Explanation:
We'll be using the converse of the pythagorean theorem.
If we had a triangle with sides a,b,c and was true, then we have a right triangle. Note: c is always the longest side
For the first answer choice we have: a = 5, b = 8, c = 12
Then,
which is false. This shows that we do not have a right triangle with sides 5,8,12. This rules out choice A. Choice C is a similar story.
Choice B on the other hand works because
We have a true statement at the end, which confirms <u>choice B</u> is a right triangle.