document.write( "Question 158810: a right triangle has hypotenuse with a measure of 20 cm and a perimeter of 47cm. find the measure of the remaining sides. \n" ); document.write( "
Algebra.Com's Answer #117017 by gonzo(654)\"\" \"About 
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draw triangle ABC where AB is the height and BC is the hypotenuse and AC is the base.
\n" ); document.write( "A is bottom left, B is top left right above A, C is bottom right.
\n" ); document.write( "let z = BC = 20cm = hypotenuse
\n" ); document.write( "let x = AC = base
\n" ); document.write( "let y = BA = height
\n" ); document.write( "let \"x%2By%2Bz+=+47\" (given)
\n" ); document.write( "this becomes \"x%2By%2B20+=+47\" (z is given as 20)
\n" ); document.write( "subtracting 20 from both sides of the equation gets \"x%2By=27\"
\n" ); document.write( "solving for either x or y gets \"y=27-x\"
\n" ); document.write( "-------------------
\n" ); document.write( "pythagorean formula states that \"z+=+sqrt%28x%5E2+%2B+y%5E2%29\"
\n" ); document.write( "this becomes \"20+=+sqrt%28x%5E2+%2B+y%5E2%29\"
\n" ); document.write( "squaring both sides of the equation, we get
\n" ); document.write( "\"400+=+x%5E2+%2B+y%5E2\" (***** this five star equation used below)
\n" ); document.write( "substituting (27-x) for y gets
\n" ); document.write( "\"400+=+x%5E2+%2B+%2827-x%29%5E2\"
\n" ); document.write( "this becomes
\n" ); document.write( "\"400+=+x%5E2+%2B+%2827%2A27%29+-54%2Ax+%2B+x%5E2\"
\n" ); document.write( "this becomes
\n" ); document.write( "\"2%2Ax%5E2+-+54%2Ax+%2B+329+=+0\"
\n" ); document.write( "i could not find any common multiples so i used the quadratic equation to solve.
\n" ); document.write( "the quadratic equation is \"x=%28%28-b%29%2Bsqrt%28b%5E2-4%2Aa%2Ac%29%29%2F%282%2Aa%29\" and \"x=%28%28-b%29-sqrt%28b%5E2-4%2Aa%2Ac%29%29%2F%282%2Aa%29\"
\n" ); document.write( "in this equation,
\n" ); document.write( "a = 2
\n" ); document.write( "b = -54
\n" ); document.write( "c = 329
\n" ); document.write( "after solving the formula (details left out for sake of brevity)
\n" ); document.write( "i got
\n" ); document.write( "x = 17.71307489, and x = 9.286925113
\n" ); document.write( "one of these becomes y, so the answers appear to be
\n" ); document.write( "x = 17.71307489, and y = 9.286925113
\n" ); document.write( "plugging these values into the original equation for x + y + z = 47 yielded 47 = 47 proving the value were good for the perimeter equation.
\n" ); document.write( "results were 17.71307489 + 9.286925113 + 20 = 47 which became 47 = 47.
\n" ); document.write( "plugging these values into the original quadratic equation solving for 400 = 400 = x^2 + y^2(the 5 start equation ***** shown above) yields
\n" ); document.write( "17.713^2 + 9.2819^2 = 400 which became 400 = 400 proving that the values for x and y are good.
\n" ); document.write( "truncated values are shown but full values were used in the calculations.
\n" ); document.write( "answer is
\n" ); document.write( "x = 17.7130
\n" ); document.write( "y = 9.2869
\n" ); document.write( "z = 20
\n" ); document.write( "perimeter = 47 checks out ok
\n" ); document.write( "z^2 = x^2 + y^2 checks out ok
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