document.write( "Question 675205: The hypotenuse of a right triangle is 9cm less than two times the shortest leg.
\n" ); document.write( "The longer leg is 36cm. Find the length of the shortest leg of the right triangle and find the hypotenuse.
\n" ); document.write( "Please show all steps.
\n" ); document.write( "Thanks
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Algebra.Com's Answer #419757 by jsmallt9(3758)\"\" \"About 
You can put this solution on YOUR website!
Let x = the length of the shortest leg. Then the length of the hypotenuse would be: 2x - 9.

\n" ); document.write( "We have expressions for all three sides of a right triangle. So they should fit in the Pythagorean equation:
\n" ); document.write( "\"%28x%29%5E2+%2B+%2836%29%5E2+=+%282x-9%29%5E2\"

\n" ); document.write( "Now we solve this for x. First we simplify:
\n" ); document.write( "\"x%5E2+%2B+1296+=+4x%5E2-36x%2B81\"
\n" ); document.write( "Now we want one side to be zero. Subtracting both terms of the left side we get:
\n" ); document.write( "\"0+=+3x%5E2-36x-1215\"
\n" ); document.write( "Now we factor (or use the Quadratic Formula). We can factor out the GCF of 3:
\n" ); document.write( "\"0+=+3%28x%5E2-12x-405%29\"
\n" ); document.write( "The second factor will factor, but not easily. (So I understand if you prefer to use the Quadratic Formula instead.)
\n" ); document.write( "\"0+=+3%28x-27%29%28x%2B15%29\"
\n" ); document.write( "From the Zero Product Property we know that one of these factors must be zero. The \"3\" will not be zero but the other two could:
\n" ); document.write( "x - 27 = 0 or x + 15 = 0
\n" ); document.write( "Solving there we get:
\n" ); document.write( "x = 27 or x = -15

\n" ); document.write( "Since x represents the shortest leg of our triangle, we will reject the negative answer. So the shortest leg is 27.

\n" ); document.write( "And we can use this value for x to find the hypotenuse:
\n" ); document.write( "2(27) - 9
\n" ); document.write( "54 - 9
\n" ); document.write( "45

\n" ); document.write( "So the shortest leg is 27 cm and the hypotenuse is 54 cm.

\n" ); document.write( "P.S. This problem can be solved very quickly if you are familiar with 3/4/5 right triangles. Not only will triangles with sides of 3, 4 and 5 be right triangles, so will any triangle that has multiples of 3, 4 and 5 for its sides.

\n" ); document.write( "Since the longer leg given to you, 36, is a multiple of 4 (the longer leg of 3/4/5 triangles), you might see if the other legs are the same multiples. 36 is 9 * 4. So let's pretend that the short leg is 9 * 3 = 27 and the hypotenuse is 9 * 5 = 45. All we have to do now is make sure that the hypotenuse is \"9cm less than two times the shortest leg\":
\n" ); document.write( "Is 2*27 - 9 = 45? Answer: Yes! So we could solve this very quickly this way. (NOTE: If the hypotenuse had not been \"9cm less than two times the shortest leg\" then we would have to solve this using algebra like the first, longer solution above.)
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