Answer:
no
Explanation:
You want to know if side lengths 26 in, 36 in, 46 in form a right triangle.
Pythagorean triple
The integer side lengths will form a right triangle if they are a Pythagorean triple, or a multiple of one.
We notice that these side lengths have a common difference of 10 in. That makes them an arithmetic sequence. The only Pythagorean triples that are an arithmetic sequence are {3, 4, 5} and its multiples. The shortest side is 3 times the common difference.
The lengths {26, 36, 46} cannot form a right triangle. The attachment shows the triangle is an obtuse triangle.
No, the triangle is not a right triangle.
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Additional comment
The side lengths will form a right triangle if and only if they satisfy the relation a² +b² = c², where a, b are the two short sides.
26² +36² = 1972 ≠ 2116 = 46²