document.write( "Question 606387: Find the height of triangle KLM.\r
\n" ); document.write( "\n" ); document.write( "They told me the triangle is isosceles, so KL and LM are congruent. The third side, KM, is 42cm. The perimeter is 112cm. From that, I figured out that KL and LM are 35cm. I'm having trouble finding the height... I tried using sine, cosine, and tangent, but I was having trouble. I split the triangle into two and tried to find a sine, cosine, or tangent of the 90 degree angle.
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Algebra.Com's Answer #382055 by Earlsdon(6294)\"\" \"About 
You can put this solution on YOUR website!
Your assumptions are good so far!
\n" ); document.write( "Now drop a line from the vertex L perpendicular to the base (KM)at point Q. This will bisect KM at Q and you will have two congruent right triangles KLQ and MLQ.
\n" ); document.write( "The hypotenuse of these right triangles is 35cm and the base of one of the right triangles is \"42%2F2+=+21\".
\n" ); document.write( "Now you can use the Pythgorean theorem to find the height (h).
\n" ); document.write( "\"%2835%29%5E2+=+%2821%29%5E2%2Bh%5E2\"
\n" ); document.write( "\"1225+=+441%2Bh%5E2\" Subtract 441 from both sides.
\n" ); document.write( "\"784+=+h%5E2\" Take the square root of both sides.
\n" ); document.write( "\"h+=+28\"
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