document.write( "Question 947539: 1.please help me to solve this problem abcd is quadrilateral prove that (ab+bc+cd+da)>(av+bd)
\n" ); document.write( "2.find the length of hypotenuse of right triangle,the other two sides are
\n" ); document.write( "9 cm,12 cm
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Algebra.Com's Answer #578200 by KMST(5328)\"\" \"About 
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1. Points A, B, C, and D are the vertices of the quadrilateral
\n" ); document.write( "(I write them as capital letters, because points are usually named that way),
\n" ); document.write( "but what point is V? Or did you mean B?
\n" ); document.write( "If ABCD is quadrilateral,
\n" ); document.write( "BD is a diagonal, and of course
\n" ); document.write( "BD < BC + CD
\n" ); document.write( "That is because a straight line is the shorter distance between two points,
\n" ); document.write( "or because the length of a side of any triangle (such as side BD of triangle BCD)
\n" ); document.write( "is less than the sum of the lengths of the other two sides (sides BC and CD).
\n" ); document.write( "Those are two ways of saying the same thing.
\n" ); document.write( "So, since BD < BC + CD,
\n" ); document.write( "then, BD < BC + CD ---> AB + BD < AB + BC + CD < AB + BC + CD +DA
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\n" ); document.write( "2. What your teacher expects is that you use a calculator and the Pythagorean theorem,
\n" ); document.write( "that says that for a right triangle,
\n" ); document.write( "the square of the length of the hypotenuse is
\n" ); document.write( "the sum of the squares of the lengths of the other two sides (called legs).
\n" ); document.write( "In your case, with the lengths in cm,
\n" ); document.write( "\"hypotenuse%5E2=9%5E2%2B12%5E2\"
\n" ); document.write( "\"hypotenuse%5E2=81%2B144\"
\n" ); document.write( "\"hypotenuse%5E2=225\"
\n" ); document.write( "\"hypotenuse=sqrt%28225%29\"
\n" ); document.write( "Now (unless you remember squares of small numbers as I do),
\n" ); document.write( "you use a calculator to find that square root, and get
\n" ); document.write( "\"hypotenuse=highlight%2815%29\" ,
\n" ); document.write( "so the length of the hypotenuse is \"highlight%2815cm%29\" .
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\n" ); document.write( "However, if you do not have to show your work,
\n" ); document.write( "and especially if you need to solve the problem quickly for a timed test,
\n" ); document.write( "there is a faster way to the answer:
\n" ); document.write( "A very popular Pythagorean triple is (3,4,5),
\n" ); document.write( "meaning that a right triangle with legs measuring 3, and 4,
\n" ); document.write( "has a hypotenuse measuring 5 (measured in whatever units you choose).
\n" ); document.write( "That triangle can be scaled up, by multiplying all measurements by the same number.
\n" ); document.write( "Multiplying times 2, we get the triple (6,8,10);
\n" ); document.write( "multiplying times 3, we get \"%22%28%22\"\"red%289%29\"\"%22%2C%22\"\"green%2812%29\"\"%22%2C%22\"\"highlight%2815%29\"\"%22%29%22\".
\n" ); document.write( "So, I do not need to to do much calculation to know that in a right triangle,
\n" ); document.write( "if the lengths of the legs are \"red%289%29\" cm, and \"green%2812%29\" cm ,
\n" ); document.write( "the length of hypotenuse is \"highlight%2815+cm%29\" .
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