Question

Which kind of triangle exists if the side measures are 3, 9, and 10?

i thought the answer was acute but my teacher marked it wrong and told me the correct answer was obtuse could someone explain why it would be obtuse?

Answer 1

Explanation:

There is a rule that if c^2 > a^2 + b^2, then it is an obtuse triangle.

*c is the longest side

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