document.write( "Question 147405: A two digit counting number has a value of 8 times the sum of its digits. If 6 times the units digit is 5 more than the tens digits, what is the number? \n" ); document.write( "
Algebra.Com's Answer #107793 by nerdybill(7384)\"\" \"About 
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A two digit counting number has a value of 8 times the sum of its digits. If 6 times the units digit is 5 more than the tens digits, what is the number?
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\n" ); document.write( "Let x = \"units\" digit
\n" ); document.write( "and y = \"tens\" digit
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\n" ); document.write( "Since we have two unknowns, we'll need two equations.
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\n" ); document.write( "From:
\n" ); document.write( "\"A two digit counting number has a value of 8 times the sum of its digits.\"
\n" ); document.write( "we get equation 1:
\n" ); document.write( "10y + x = 8(x+y)
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\n" ); document.write( "From:
\n" ); document.write( "\"6 times the units digit is 5 more than the tens digits\"
\n" ); document.write( "we get equation 2:
\n" ); document.write( "6x - 5 = y
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\n" ); document.write( "From equation 2, we see that y is equal to (6x+5) -- substitute this into equation 1 and solve for x:
\n" ); document.write( "10y + x = 8(x+y)
\n" ); document.write( "10(6x-5) + x = 8(x+(6x-5))
\n" ); document.write( "(60x-50) + x = 8(7x-5)
\n" ); document.write( "61x-50 = 56x-40
\n" ); document.write( "5x = 10
\n" ); document.write( "x = 2
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\n" ); document.write( "To find y, substitute the above into equation 2:
\n" ); document.write( "6x - 5 = y
\n" ); document.write( "6(2) - 5 = y
\n" ); document.write( "12 - 5 = y
\n" ); document.write( "7 = y
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\n" ); document.write( "Your 2 digit number is: 72\r
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