Answer:
x = 25
The lengths form a pythagorean triple
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Step-by-step explanation:
Use the pythagorean theorem to get the following
Since we end up with a whole number, we do form a pythagorean triple of 15,20,25 or you can write it as 15-20-25
A pythagorean triple is where a,b,c are all integers that satisfy the pythagorean theorem above.
This is not a primitive pythagorean triple because we could divide all three values by the GCF 3 to get the triple 3-4-5. The keyword for this paragraph is "primitive".