document.write( "Question 225261: find 2 consecutive integers such that three times the square of the first is equal to seven more than five times the second.\r
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Algebra.Com's Answer #168275 by drj(1380)\"\" \"About 
You can put this solution on YOUR website!
Find 2 consecutive integers such that three times the square of the first is equal to seven more than five times the second.\r
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\n" ); document.write( "\n" ); document.write( "Step 1. Let \"n\" be the first integer.\r
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\n" ); document.write( "\n" ); document.write( "Step 2. Let \"n%2B1\" be the next consecutive integer\r
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\n" ); document.write( "\n" ); document.write( "Step 3. Let \"3n%5E2\" be three times the square of the first.\r
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\n" ); document.write( "\n" ); document.write( "Step 4. Let \"7%2B5%28n%2B1%29\" be seven more than five times the second.\r
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\n" ); document.write( "\n" ); document.write( "Step 5. Then \"3n%5E2=7%2B5%28n%2B1%29\" since three times the square of the first is equal to seven more than five times the second.\r
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\n" ); document.write( "\n" ); document.write( "Step 6. Solving the equation in Step 5 yields the following steps.\r
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\n" ); document.write( "\n" ); document.write( "\"3n%5E2=7%2B5%28n%2B1%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"3n%5E2=7%2B5n%2B5=12%2B5n\"\r
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\n" ); document.write( "\n" ); document.write( "Subtract 5n+12 from both sides of the equation\r
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\n" ); document.write( "\n" ); document.write( "\"3n%5E2-5n-12=12%2B5n-5n-12\"\r
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\n" ); document.write( "\n" ); document.write( "\"3n%5E2-5n-12=0\"\r
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\n" ); document.write( "\n" ); document.write( "Step 7. To solve use the quadratic equation given as\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"\r
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\n" ); document.write( "\n" ); document.write( "where a=3, b=-5, and c=-12\r
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"1x%5E2%2B-2x%2B-3+=+0\") has the following solutons:
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\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%28-2%29%5E2-4%2A1%2A-3=16\".
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\n" ); document.write( " Discriminant d=16 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--2%2B-sqrt%28+16+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-2%29%2Bsqrt%28+16+%29%29%2F2%5C1+=+3\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-2%29-sqrt%28+16+%29%29%2F2%5C1+=+-1\"
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\n" ); document.write( " Quadratic expression \"1x%5E2%2B-2x%2B-3\" can be factored:
\n" ); document.write( " \"1x%5E2%2B-2x%2B-3+=+1%28x-3%29%2A%28x--1%29\"
\n" ); document.write( " Again, the answer is: 3, -1.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-2%2Ax%2B-3+%29\"

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\n" ); document.write( "\n" ); document.write( "With n=3 then n+1=4. Check \"3n%5E2=7%2B5%28n%2B1%29\" if true so \"3%2A3%5E2=7%2B5%2A4\" or \"27=27\" which is a true statement.\r
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\n" ); document.write( "\n" ); document.write( "With n=-1 then n+1=0 Check \"3n%5E2=7%2B5%28n%2B1%29\" if true so \"3%2A%28-1%29%5E2=7%2B5%2A0\" or \"3=7\" which is not a true statement.\r
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\n" ); document.write( "\n" ); document.write( "Step 8. ANSWER: The numbers are 3 and 4\r
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\n" ); document.write( "\n" ); document.write( "I hope the above steps were helpful.\r
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\n" ); document.write( "\n" ); document.write( "For FREE Step-By-Step videos in Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.\r
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\n" ); document.write( "\n" ); document.write( "And good luck in your studies!\r
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\n" ); document.write( "\n" ); document.write( "Respectfully,
\n" ); document.write( "Dr J\r
\n" ); document.write( "\n" ); document.write( "http://www.FreedomUniversity.TV\r
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