document.write( "Question 1035904: This question was in my daughters Year 8 maths test today and I am of no help\r
\n" ); document.write( "\n" ); document.write( "A father observes that the ratio of his age to his daughters age is 3:2 right now. But his daughter observes that in 8 years time their ages will be 7:5
\n" ); document.write( "Is this enough information to determine their ages?
\n" ); document.write( "If Yes, what are their ages
\n" ); document.write( "If No, explain why\r
\n" ); document.write( "\n" ); document.write( "Thanks for your help
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Algebra.Com's Answer #650512 by josgarithmetic(39617)\"\" \"About 
You can put this solution on YOUR website!
Grade 8 level exercise, not sure. Variables would be helpful.\r
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\n" ); document.write( "\n" ); document.write( "y for Father's age now.
\n" ); document.write( "x for daughter's age now.\r
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\n" ); document.write( "\n" ); document.write( "Transcribe or translate the description, literally.
\n" ); document.write( "\"highlight_green%28system%28y%2Fx=3%2F2%2C%28y%2B8%29%2F%28x%2B8%29=7%2F5%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "This is a system of two of what really are LINEAR equations in two unknown variables.
\n" ); document.write( "If your daughter is in a Pre-Algebra course, maybe she will understand this discussion just
\n" ); document.write( "given, and could solve the system of equations. \r
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\n" ); document.write( "\n" ); document.write( "---
\n" ); document.write( "REVIEWING WHAT WAS JUST POSTED:\r
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\n" ); document.write( "\n" ); document.write( "(1)
\n" ); document.write( "Assigned variables for the current ages of Father and his Daughter\r
\n" ); document.write( "\n" ); document.write( "(2)
\n" ); document.write( "Translated the description of the problem into equations\r
\n" ); document.write( "\n" ); document.write( "(3)
\n" ); document.write( "Need to SOLVE the system of equations (not yet shown)\r
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\n" ); document.write( "\n" ); document.write( "You want to solve the system of equations and to know if in fact, the system can be solved. Let us try some arithmetic or algebra steps.\r
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\n" ); document.write( "\n" ); document.write( "Try using multiplicative inverse property.
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\n" ); document.write( "-
\n" ); document.write( "\"system%28y=3x%2F2%2C5%28y%2B8%29=%28x%2B8%29%2A7%29\"
\n" ); document.write( "-
\n" ); document.write( "Simplify the second equation.
\n" ); document.write( "\"system%28y=3x%2F2%2C5y%2B40=7x%2B56%29\"
\n" ); document.write( "-\r
\n" ); document.write( "\n" ); document.write( "Substitute for y into the second equation.
\n" ); document.write( "\"5%283x%2F2%29%2B40=7x%2B56\"
\n" ); document.write( "continue algebraic steps, not saying the names of the properties being used (hopefully they are not needed to be identified...)
\n" ); document.write( "\"15x%2F2%2B40=7x%2B56\"
\n" ); document.write( "\"15x%2B80=14x%2B112\"
\n" ); document.write( "\"15x-14x%2B80=112\"
\n" ); document.write( "\"x%2B80=112\"
\n" ); document.write( "\"x=112-80\"
\n" ); document.write( "\"highlight%28x=32%29\"--------one of the results, the daughter's age now.\r
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\n" ); document.write( "\n" ); document.write( "Use the first equation found before the system was simplified, being y=3x/2 and evaluate y, knowing the found value for x:
\n" ); document.write( "\"y=3%2832%29%2F2\"
\n" ); document.write( "\"y=%283%2A32%29%2F2\"
\n" ); document.write( "\"y=%283%2A2%2A16%29%2F2\"
\n" ); document.write( "\"y=3%2A16\"
\n" ); document.write( "\"highlight%28y=48%29\"-------------result for father's age now.
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