Answer: C. 8-14-17
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Step-by-step explanation:
Choice A is a non-answer because 3-4-5 does represent a right triangle. We can see so from the Pythagorean theorem
a^2+b^2 = c^2
3^2+4^2 = 5^2
9+16 = 25
25 = 25
We get a true equation, so (a,b,c) = (3,4,5) is a solution to a^2+b^2 = c^2
This confirms a 3-4-5 triangle is a right triangle.
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The same steps can be used to show 6-8-10 is also a right triangle (note how each value has been doubled compared to 3-4-5). We can cross choice B off the list.
We can also see that choice D is a non-answer as well.
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Choice C is the only thing left. The proper Pythagorean triple is actually 8-15-17.
Let's see what happens when a = 8, b = 14, c = 17
a^2+b^2 = c^2
8^2+14^2 = 17^2
64+196 = 289
260 = 289 .... false equation
We get a false equation, so a = 8, b = 14, c = 17 does not form a right triangle.