document.write( "Question 410283: Terri is two years older than Ginnie. Joan is twice Ginnie's age. How old is Ginnie if the sum of the squares of the three ages is 420? \n" ); document.write( "
Algebra.Com's Answer #288566 by josmiceli(19441)\"\" \"About 
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Let \"t\" = Terri's age
\n" ); document.write( "Let \"g\" = Ginnie's age
\n" ); document.write( "Let \"j\" = Joan's age
\n" ); document.write( "given:
\n" ); document.write( "\"t+=+g+%2B+2\"
\n" ); document.write( "\"j+=+2g\"
\n" ); document.write( "\"t%5E2+%2B+g%5E2+%2B+j%5E2+=+420\"
\n" ); document.write( "--------------------
\n" ); document.write( "\"%28g+%2B+2%29%5E2+%2B+g%5E2+%2B+%282g%29%5E2+=+420\"
\n" ); document.write( "\"g%5E2+%2B+4g+%2B+4+%2B+g%5E2+%2B+4g%5E2+=+420\"
\n" ); document.write( "\"6g%5E2+%2B+4g+-+416+=+0\"
\n" ); document.write( "\"3g%5E2+%2B+2g+-+208+=+0\"
\n" ); document.write( "Use quadratic formula
\n" ); document.write( "\"g+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "\"a+=+3\"
\n" ); document.write( "\"b+=+2\"
\n" ); document.write( "\"c+=+-208\"
\n" ); document.write( "\"g+=+%28-2+%2B-+sqrt%28+2%5E2-4%2A3%2A%28-208%29+%29%29%2F%282%2A3%29+\"
\n" ); document.write( "\"g+=+%28-2+%2B-+sqrt%28+4+%2B+2496+%29%29%2F+6+\"
\n" ); document.write( "\"g+=+%28-2+%2B+50%29%2F+6+\"
\n" ); document.write( "\"g+=+48%2F6\"
\n" ); document.write( "\"g+=+8\"
\n" ); document.write( "and
\n" ); document.write( "\"j+=+2g\"
\n" ); document.write( "\"j+=+16\"
\n" ); document.write( "and
\n" ); document.write( "\"t+=+g+%2B+2\"
\n" ); document.write( "\"t+=+10\"
\n" ); document.write( "Ginnie is 8 yrs old
\n" ); document.write( "check answer:
\n" ); document.write( "\"t%5E2+%2B+g%5E2+%2B+j%5E2+=+420\"
\n" ); document.write( "\"10%5E2+%2B+8%5E2+%2B+16%5E2+=+420\"
\n" ); document.write( "\"100+%2B+64+%2B+256+=+420\"
\n" ); document.write( "\"420+=+420\"
\n" ); document.write( "OK
\n" ); document.write( "
\n" );