It is known that the three sides a, B and C of △ ABC satisfy A2 + B2 + C2 = 10A + 24B + 26c-338. Please judge the shape of △ ABC and explain the reason

The reason is: ∵ A2 + B2 + C2 = 10A + 24B + 26c-338, ∵ a2-10a + 25 + b2-24b + 144 + c2-26c + 169 = 0, ∵ 52 + 122 = 132, ∵ ABC is a right triangle

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