document.write( "Question 915250: The units digit of a two digit number is 5 more than the tens digit. If the digits are reversed the new number is devided by the original the qoutient us 2 and the remainder is 7. What is the original number? \n" ); document.write( "
Algebra.Com's Answer #555505 by lwsshak3(11628)\"\" \"About 
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The units digit of a two digit number is 5 more than the tens digit. If the digits are reversed and the new number is divided by the original, the qoutient is 2 and the remainder is 7. What is the original number?
\n" ); document.write( "***
\n" ); document.write( "let u=units digit
\n" ); document.write( "let t=tens digit
\n" ); document.write( "u=t+5
\n" ); document.write( "original number=10t+u
\n" ); document.write( "new number=10u+t
\n" ); document.write( "\"%2810u%2Bt%29%2F%2810t%2Bu%29=2%2B%287%2F%2810t%2Bu%29%29\"
\n" ); document.write( "\"%2810%28t%2B5%29%2Bt%29%2F%2810t%2Bt%2B5%29=2%2B%287%2F%2810t%2Bt%2B5%29%29\"
\n" ); document.write( "\"%2810t%2B50%2Bt%29%2F%2810t%2Bt%2B5%29=2%2B%287%2F%2810t%2Bt%2B5%29%29\"
\n" ); document.write( "\"%2811t%2B50%29%2F%2811t%2B5%29=2%2B%287%2F%2811t%2B5%29%29\"
\n" ); document.write( "\"%2811t%2B50%29%2F%2811t%2B5%29=%2822t%2B17%29%2F%2811t%2B5%29%29\"
\n" ); document.write( "(11t+5)(22t+17)=(11t+50)(11t+5)
\n" ); document.write( "242t^2+297t+85=121t^2+605t+250
\n" ); document.write( "121t^2-308t-165=0
\n" ); document.write( "solve for t by quadratic formula:
\n" ); document.write( "\"t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "a=121, b=-308, c=165
\n" ); document.write( "ans:
\n" ); document.write( "t=-55/121≈-0.4545(reject)
\n" ); document.write( "or
\n" ); document.write( "t=3
\n" ); document.write( "u=t+5=8
\n" ); document.write( "Check:
\n" ); document.write( "original number=38
\n" ); document.write( "new number=83
\n" ); document.write( "new number/original number=83/38=2+Remainder=7
\n" ); document.write( " \n" ); document.write( "
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