document.write( "Question 1171698: Can you please help me out with this sum, i'm a little confused on how to do it...thank you in advance :))\r
\n" ); document.write( "\n" ); document.write( "A square has diagonals of length 10 cm. find the sides of the square.
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Algebra.Com's Answer #796604 by math_tutor2020(3817)\"\" \"About 
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\n" ); document.write( "x = side length of the square
\n" ); document.write( "Any square has all four sides the same length, so each side is x centimeters long.
\n" ); document.write( "It doesn't make sense to have x be negative, so we'll say x > 0.\r
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\n" ); document.write( "\n" ); document.write( "Draw a square with one diagonal only. We have the square divided into two congruent right triangles. Focus on one of those right triangles.\r
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\n" ); document.write( "\n" ); document.write( "This right triangle has congruent legs (x cm each) and a hypotenuse that is 10 cm long.
\n" ); document.write( "We'll let
\n" ); document.write( "a = x
\n" ); document.write( "b = x
\n" ); document.write( "c = 10
\n" ); document.write( "which will be plugged into the Pythagorean theorem to solve for x.\r
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\n" ); document.write( "\n" ); document.write( "a^2 + b^2 = c^2
\n" ); document.write( "x^2 + x^2 = 10^2
\n" ); document.write( "2x^2 = 100
\n" ); document.write( "x^2 = 100/2
\n" ); document.write( "x^2 = 50
\n" ); document.write( "x = sqrt(50) .... applying the square root, keep in mind that x > 0
\n" ); document.write( "x = sqrt(25*2)
\n" ); document.write( "x = sqrt(25)*sqrt(2)
\n" ); document.write( "x = 5*sqrt(2)\r
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\n" ); document.write( "\n" ); document.write( "Each leg is exactly 5*sqrt(2) cm long\r
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\n" ); document.write( "\n" ); document.write( "Therefore, each side of the square is 5*sqrt(2) cm long.\r
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\n" ); document.write( "\n" ); document.write( "This is known as the exact answer because we don't have any decimal approximations going on. \r
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\n" ); document.write( "\n" ); document.write( "Use of your calculator should lead to the rough approximation of
\n" ); document.write( "5*sqrt(2) = 7.0710678
\n" ); document.write( "Note that
\n" ); document.write( "sqrt(50) = 7.0710678
\n" ); document.write( "to help confirm that sqrt(50) = 5*sqrt(2)\r
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\n" ); document.write( "\n" ); document.write( "Exact Answer: 5*sqrt(2) cm
\n" ); document.write( "Approximate Answer: 7.0710678 cm
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