evaluate cot ( Cos^-1( -15/17)) enter your answer as a fraction using the slash bar (/)

Question

anonymous · Answer

inverse cosine means it's going to give you the angle that yields that ratio of sides. Cos is adjacent over hypotenuse, so draw a triangle with -15 as the adjacent side and 17 as the hypotenuse:
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anonymous · Answer

Now, simply use the pythagorean theorem to solve for the third side.

anonymous · Answer

And then use the definition of cot = adjacent over opposite.

anonymous · Answer

i tried but gave me 6/4 I'm lost :/

anonymous · Answer

Show me the math you did for solving for the third side.

anonymous · Answer

Pythagorean theorem: a^2 + b^2 = c^2

anonymous · Answer

is in the trash :/

paxpolaris · Answer

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Finding the third side: 
$$\Large x=\sqrt{17^2-15^2}$$

anonymous · Answer

lols, okay. Well try it again.

anonymous · Answer

i don't have the calculator anymore  :( and im helping my bro with his Work

anonymous · Answer

Use google as a calculator =) Or use wolframalpha.com

anonymous · Answer

hint: to do square roots, type sqrt(whatever)

anonymous · Answer

:(

anonymous · Answer

Don't pout at me. Gimme some effort.

paxpolaris · Answer

$$\Large 17^2 =\left( 15+2 \right)^2=225+60+4$$

anonymous · Answer

289 but i need it in fractions

paxpolaris · Answer

$$x= \sqrt{289-225}$$

anonymous · Answer

-_-

paxpolaris · Answer

x is the third side.... first find it the you can solve for cotangent

anonymous · Answer

still dont get it -_______________________-