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If a triangle has side lengths 7, 10, and 12, is it a right triangle??

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Answer:

No. Remember, a right angle must have a 90 degree angle. We can find the lengths with the Pythagorean Theorem.

Explanation:

Given the length 7, 10, and 12, we can assume that 12 is the hypotenuse (it is the longest length).

- we can use 7 and 10 interchangeably.

Fill in the equation,
a^2 + b^2 = c^2

where c = 12, and a or b = 7 or 10.

To indicate if the given lengths would form a right angle, we can only input 7 or 10, not both.

Therefore,
7^2 + b^2 = 12^2 or
10^2 + b^2 = 12^2


7^2 + b^2 = 12^2 ==> 49 + b^2 = 144 ==> b=
\sqrt{95 ==> 9.746

b= 9.7, not 10.


10^2 + b^2 = 12^2 ==> 100 + b^2 = 144 ==> b =
\sqrt{44 ==> 6.633

b= 6.6, not 7.

Therefore, the lengths 7, 10, and 12, does NOT make a right triangle.

Hope this helps!

User Greg Hornby
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