Need help FAST not sure

9514 1404 393

  7.  obtuse

  8.  right

  9.  acute

Step-by-step explanation:

You can look at the difference ...

  a^2 + b^2 -c^2

where c is the longest side. You can classify the triangle based on the result:

  > 0 -- acute

  = 0 -- right

  < 0 -- obtuse

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7. 7^2 +9^2 -15^2 = 49 +81 -225 = -95  ⇒  obtuse

8. 3^2 +4^2 -5^2 = 9 +16 -25 = 0  ⇒  right

9. 4^2 +5^2 -6^2 = 16 +25 -36 = 5  ⇒  acute

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There are several triangle solver apps and web sites available. Your graphing calculator may also solve triangles for you.

the answer i believe is 27 units.

step-by-step explanation: