document.write( "Question 648729: A father is four times as old as his daughter. In 6 years, he will be three times as old as she is. How old is the daughter now
\n" ); document.write( " \n" ); document.write( "

Algebra.Com's Answer #406763 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+f+\"$ = the Father's age now
\n" ); document.write( "Let $\"+d+\"$ = the Daughter's age now
\n" ); document.write( "given:
\n" ); document.write( "(1) $\"+f+=+4d+\"$
\n" ); document.write( "(2) $\"+f+%2B+6+=+3%2A%28+d+%2B+6+%29+\"$
\n" ); document.write( "-----------------------
\n" ); document.write( "(2) $\"+f+%2B+6+=+3d+%2B+18+\"$
\n" ); document.write( "(2) $\"+f+=+3d+%2B+12+\"$
\n" ); document.write( "Substitute (1) into (2)
\n" ); document.write( "(2) $\"+4d+=+3d+%2B+12+\"$
\n" ); document.write( "(2) $\"+d+=+12+\"$
\n" ); document.write( "and, since
\n" ); document.write( "(1) $\"+f+=+4d+\"$
\n" ); document.write( "(1) $\"+f+=+4%2A12+\"$
\n" ); document.write( "(1) $\"+f+=+48+\"$
\n" ); document.write( "--------------
\n" ); document.write( "The Daughter is 12 now
\n" ); document.write( "check:
\n" ); document.write( "(2) $\"+f+%2B+6+=+3%2A%28+d+%2B+6+%29+\"$
\n" ); document.write( "(2) $\"+f+%2B+6+=+3%2A%28+12+%2B+6+%29+\"$
\n" ); document.write( "(2) $\"+f+%2B+6+=+36+%2B+18+\"$
\n" ); document.write( "(2) $\"+f+=+54+-+6+\"$
\n" ); document.write( "(2) $\"+f+=+48+\"$
\n" ); document.write( "OK
\n" ); document.write( " \n" ); document.write( "

\n" );