Is the triangle acute, right or obtuse?
Compare the sum of the squares of the two shorter sides with the square of the longest side. Equal: right. Greater: acute. Less: obtuse.
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A triangle has sides of 5, 17 and 20. Is it acute, right or obtuse? Write acute, right or obtuse.
Answer: obtuse
A triangle has sides of 13, 19 and 8. Is it acute, right or obtuse? Write acute, right or obtuse.
Answer: obtuse
A triangle has sides of 6, 8 and 8. Is it acute, right or obtuse? Write acute, right or obtuse.
Answer: acute
Tip: Compare the sum of the squares of the two shorter sides with the square of the longest side. Equal: right. Greater: acute. Less: obtuse.
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