SOLUTION: Two sides of a triangle are 12 and 15 cm long. Which measurement can be the length of the third side?

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Question 88043: Two sides of a triangle are 12 and 15 cm long. Which measurement can be the length of the third side?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Since we have a triangle with legs of 12 , 15 and a hypotenuse of x(our unknown side), we can use Pythagoreans theorem to find the unknown side.
Pythagoreans theorem
a%5E2%2Bb%5E2=c%5E2

12%5E2%2B15%5E2=c%5E2 Plug in a=12 and b=15 and lets solve for c
1+4+4+%2B+2+2+5+=++c++%5E+2 Square each individual term



3+6+9+=++c++%5E+2 Combine like terms


s+q+r+t+%28+3+6+9+%29+=+s+q+r+t+%28++c++%5E+2+%29 Take the square root of both sides


3%2Asqrt%2841%29=c Simplify the square root


Which approximates to...
1+9+.+2+0+9+3+7+2+7+1+2+2+9+8+5+=+c

So our answer is
c+=+1+9+.+2+0+9+3+7+2+7+1+2+2+9+8+5