document.write( "Question 982901: Maggie's brother is 3 years younger than twice her age. The sum of their ages is 24. How old is Maggie? \n" ); document.write( "

Algebra.Com's Answer #603697 by ikleyn(52797) $\"\"$ $\"About$

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\n" ); document.write( "\n" ); document.write( "Let x be the Maggie's age and y be her brother's age. \r
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\n" ); document.write( "\n" ); document.write( "Then you have two equations:\r
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\n" ); document.write( "\n" ); document.write( "1. y = 2x -3, and \r
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\n" ); document.write( "\n" ); document.write( "2. x + y = 24.\r
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\n" ); document.write( "\n" ); document.write( "So, you need to solve the system of two linear equations in two unknowns \r
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\n" ); document.write( "\n" ); document.write( " $\"system%28y+=+2x+-+3%2C%0D%0Ax+%2B+y+=+24%29\"$ . \r
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\n" ); document.write( "\n" ); document.write( "Express y from the second equation y = 24 - x and substitute it into the first equation. You will get\r
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\n" ); document.write( "\n" ); document.write( "24 - x = 2x - 3.\r
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\n" ); document.write( "\n" ); document.write( "Simplify it step by step:\r
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\n" ); document.write( "\n" ); document.write( "24 + 3 = 2x + x,\r
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\n" ); document.write( "\n" ); document.write( "27 = 3x,\r
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\n" ); document.write( "\n" ); document.write( "x = $\"27%2F3\"$ = 9.\r
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\n" ); document.write( "\n" ); document.write( "Answer. Maggie is 9 years old.\r
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