document.write( "Question 673179: Jenny is three times as old as her daughter Krystal. Four years ago she was four times as old as Krystal. How old is each now? \n" ); document.write( "

Algebra.Com's Answer #418508 by rm29924(97) $\"\"$ $\"About$

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let x = Krystal's age now
\n" ); document.write( "Jenny is three times as old so Jenny's current age = 3x\r
\n" ); document.write( "\n" ); document.write( "Jenny's age 4 yrs ago = 3x - 4
\n" ); document.write( "Krystal's age 4 yrs ago = x-4\r
\n" ); document.write( "\n" ); document.write( "four years ago she was four times as old as Krystal
\n" ); document.write( "3x-4 = 4(x-4)
\n" ); document.write( " multiply by 4
\n" ); document.write( "3x-4 = 4x-16
\n" ); document.write( "add 16 to both sides
\n" ); document.write( "3x+12 = 4x
\n" ); document.write( "subtract 3x from both sides
\n" ); document.write( "12 = x\r
\n" ); document.write( "\n" ); document.write( "Krystal's age now is 12
\n" ); document.write( "Jenny's age now is 3(12) = 36\r
\n" ); document.write( "\n" ); document.write( "check work:
\n" ); document.write( "3x-4 = 4(x-4)
\n" ); document.write( "3(12)-4 = 4(12-4)
\n" ); document.write( "36-4 = 32
\n" ); document.write( "32=32\r
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