document.write( "Question 618648: the ratio of two sides of a parallelogram is 3.5 and its perimeter is 48 cm . find the sides of the pallelogram. \n" ); document.write( "
Algebra.Com's Answer #389068 by math-vortex(648)\"\" \"About 
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Hi, there--
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\n" ); document.write( "Recall that a parallelogram has two pairs of parallel sides. We will use two variables to solve this problem.
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\n" ); document.write( "Let x be the length of each of the shorter pair of parallel sides.
\n" ); document.write( "Let y be the length of each of the longer pair of parallel sides.
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\n" ); document.write( "We will use the information given in the problem to write two equations that model the problem. The perimeter (48 cm.) is the sum of the four sides, so
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\n" ); document.write( "\"48=x%2Bx%2By%2By\"
\n" ); document.write( "\"2x%2B2y=48\"
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\n" ); document.write( "The ratio of two sides of the parallelogram is 3.5. Since the parallel sides of a parallelogram have equal length, we know that we are comparing the lengths x and y here, so
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\n" ); document.write( "\"y%2Fx=3.5\"
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\n" ); document.write( "NOTE: We set up the variable so that y is longer than x. The ratio is greater than 1 so we know that we are comparing the longer side to the shorter one.
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\n" ); document.write( "Now we have two variables and two equations. We can solve the system to find the values of x and y.
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\n" ); document.write( "Rewrite the first equation in terms of x.
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\n" ); document.write( "\"2x%2B2y=48\"
\n" ); document.write( "\"2y=48-2x\"
\n" ); document.write( "\"y=24-x\"
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\n" ); document.write( "Substitute 24-x for y in the second equation.
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\n" ); document.write( "\"y%2Fx=3.5\"
\n" ); document.write( "\"%2824-x%29%2Fx=3.5\"
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\n" ); document.write( "Solve for x.
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\n" ); document.write( "\"24-x=3.5x\"
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\n" ); document.write( "I'm not a fan of decimal coefficients, so I multiply every term by 2.
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\n" ); document.write( "\"48-2x=7x\"
\n" ); document.write( "\"48=9x\"
\n" ); document.write( "\"x=48%2F9=16%2F3\"
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\n" ); document.write( "We now know that the shorter sides have a length of 16/3 cm. Substitute 16/3 for x in the first equation.
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\n" ); document.write( "\"2x%2B2y=48\"
\n" ); document.write( "\"2%2816%2F3%29%2B2y=48\"
\n" ); document.write( "\"32%2F3%2B2y=48\"
\n" ); document.write( "\"2y=48-32%2F3\"
\n" ); document.write( "\"y=24-32%2F6=56%2F3\"
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\n" ); document.write( "According to this equation, the length of the longer side is 56/3 cm.
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\n" ); document.write( "Now we side to check our work. The perimeter is 48 cm.
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\n" ); document.write( "\"16%2F3%2B16%2F3%2B56%2F3%2B56%2F3=144%2F3\"
\n" ); document.write( "\"144%2F3=48\"
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\n" ); document.write( "The perimeter checks out. Now we need to check that the ratio of the two sides reduces to 3.5.
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\n" ); document.write( "\"%2856%2F3%29%2F%2816%2F3%29=56%2F16\"
\n" ); document.write( "\"56%2F16=3.5\"
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\n" ); document.write( "Check! So the lengths of the sides of the parallelogram are 16/3 cm and 56/3 cm.
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\n" ); document.write( "Hope this helps. Feel free to email me if you have questions about this.
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\n" ); document.write( "Ms.Figgy
\n" ); document.write( "math.in.the.vortex@gmail.com\r
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