document.write( "Question 973229: What is the smallest of three consecutive positive numbers if the product of the first and third is one less than eight times the second? \n" ); document.write( "
Algebra.Com's Answer #595482 by crystal5213(2)\"\" \"About 
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The smallest number is equal to 7.\r
\n" ); document.write( "\n" ); document.write( "Explanation:\r
\n" ); document.write( "\n" ); document.write( "For this problem, I'll be using variables to represent the numbers: x, y, and z. But since they are consecutive, y=x+1, and z=x+2, so the numbers can be written as x, x+1, and x+2. \r
\n" ); document.write( "\n" ); document.write( "According to the problem, the product of the first and third number (\"x%28x%2B2%29\" or \"x%5E2%2B2x\") is equal to one less than eight times the second number (\"8%28x%2B1%29-1%29\" or \"8x%2B7\")
\n" ); document.write( "We can set the problem up like this:
\n" ); document.write( "\"x%5E2%2B2x=8x%2B7\"
\n" ); document.write( "Now we can solve it like an algebraic equation instead of a word problem. Start by moving the variable to one side of the equation by subtracting 8x from both sides, resulting in:
\n" ); document.write( "\"x%5E2-6x=7\"
\n" ); document.write( "Since there is a variable squared, we should use the quadratic formula. So we will have to subtract 7 as well, so that 0 will be on one side of the equal sign.
\n" ); document.write( "\"x%5E2-6x-7=0\"
\n" ); document.write( "According to the quadratic equation, if \"Ax%5E2%2BBx%2BC=0%2C\" then \"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "Now, we plug in the numbers.
\n" ); document.write( "\"x+=+%286+%2B-+sqrt%28+%28-6%29%5E2-4%2A1%2A%28-7%29+%29%29%2F%282%2A1%29+\"
\n" ); document.write( "in this case, a equals one because there is no number before \"x%5E2\", so the coefficient must be 1. b is -6 since that is the coefficient for x, and c is -7.
\n" ); document.write( "Finally, after using a calculator to solve the equation, we get
\n" ); document.write( "\"x=7\"
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