document.write( "Question 390980: The larger of two numbers is 5 more than twice the smaller. The square of the smaller is equal to the larger. Find the numbers \n" ); document.write( "
Algebra.Com's Answer #277304 by MathLover1(20850)\"\" \"About 
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\n" ); document.write( "let larger number be \"y\" and smaller number \"x\"\r
\n" ); document.write( "\n" ); document.write( "if the larger of is {{5}}} more than twice the smaller number, we have:\r
\n" ); document.write( "\n" ); document.write( "\"y+=+2x+%2B+5\" ..........(1)\r
\n" ); document.write( "\n" ); document.write( "if the square of the smaller is equal to the larger,we have \r
\n" ); document.write( "\n" ); document.write( "\"y+=+x%5E2\".........(2)\r
\n" ); document.write( "\n" ); document.write( "solve the system:\r
\n" ); document.write( "\n" ); document.write( "\"y+=+2x+%2B+5\" ..........(1)\r
\n" ); document.write( "\n" ); document.write( "\"y+=+x%5E2\".........(2).......substitute in (1)\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2=+2x+%2B+5\" ..........(1).solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2+-5+=+2x+\" \r
\n" ); document.write( "\n" ); document.write( "\"x%5E2+-2x++-5+=+0+\" \r
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Solved by pluggable solver: Quadratic Formula
Let's use the quadratic formula to solve for x:

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\n" ); document.write( " Starting with the general quadratic
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\n" ); document.write( " \"ax%5E2%2Bbx%2Bc=0\"
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\n" ); document.write( " the general solution using the quadratic equation is:
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\n" ); document.write( " \"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"
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\n" ); document.write( " So lets solve \"x%5E2-2%2Ax-5=0\" ( notice \"a=1\", \"b=-2\", and \"c=-5\")
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\n" ); document.write( " \"x+=+%28--2+%2B-+sqrt%28+%28-2%29%5E2-4%2A1%2A-5+%29%29%2F%282%2A1%29\" Plug in a=1, b=-2, and c=-5
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\n" ); document.write( " \"x+=+%282+%2B-+sqrt%28+%28-2%29%5E2-4%2A1%2A-5+%29%29%2F%282%2A1%29\" Negate -2 to get 2
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\n" ); document.write( " \"x+=+%282+%2B-+sqrt%28+4-4%2A1%2A-5+%29%29%2F%282%2A1%29\" Square -2 to get 4 (note: remember when you square -2, you must square the negative as well. This is because \"%28-2%29%5E2=-2%2A-2=4\".)
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\n" ); document.write( " \"x+=+%282+%2B-+sqrt%28+4%2B20+%29%29%2F%282%2A1%29\" Multiply \"-4%2A-5%2A1\" to get \"20\"
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\n" ); document.write( " \"x+=+%282+%2B-+sqrt%28+24+%29%29%2F%282%2A1%29\" Combine like terms in the radicand (everything under the square root)
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\n" ); document.write( " \"x+=+%282+%2B-+2%2Asqrt%286%29%29%2F%282%2A1%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)
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\n" ); document.write( " \"x+=+%282+%2B-+2%2Asqrt%286%29%29%2F2\" Multiply 2 and 1 to get 2
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\n" ); document.write( " So now the expression breaks down into two parts
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\n" ); document.write( " \"x+=+%282+%2B+2%2Asqrt%286%29%29%2F2\" or \"x+=+%282+-+2%2Asqrt%286%29%29%2F2\"
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\n" ); document.write( " Now break up the fraction
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\n" ); document.write( " \"x=%2B2%2F2%2B2%2Asqrt%286%29%2F2\" or \"x=%2B2%2F2-2%2Asqrt%286%29%2F2\"
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\n" ); document.write( " Simplify
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\n" ); document.write( " \"x=1%2Bsqrt%286%29\" or \"x=1-sqrt%286%29\"
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\n" ); document.write( " So the solutions are:
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\n" ); document.write( " \"x=1%2Bsqrt%286%29\" or \"x=1-sqrt%286%29\"
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\n" ); document.write( "\n" ); document.write( "\"x1=+1+%2Bsqrt%286%29=1%2B2.45\"\r
\n" ); document.write( "\n" ); document.write( "\"x1=+3.45\"..................................\r
\n" ); document.write( "\n" ); document.write( "\"x2=+1+%2Bsqrt%286%29=1-2.45\"\r
\n" ); document.write( "\n" ); document.write( "\"x2=+-1.45\"...................................\r
\n" ); document.write( "\n" ); document.write( "find \"y\"\r
\n" ); document.write( "\n" ); document.write( "\"y1+=+%283.45%29%5E2+=+11.9\"\r
\n" ); document.write( "\n" ); document.write( "\"y2+=+%28-1.45%29%5E2+=+2.1025\"\r
\n" ); document.write( "\n" ); document.write( "check:\r
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\n" ); document.write( "\n" ); document.write( "\"11.9=+2%28+3.45%29%2B+5\" ..........(1)...plug in \"x1=+3.45\"and\"y1+=+11.9\"\r
\n" ); document.write( "\n" ); document.write( "\"11.9=+6.9+%2B+5\" \r
\n" ); document.write( "\n" ); document.write( "\"11.9=+11.9+\" \r
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\n" ); document.write( "\n" ); document.write( "\"y=+%28x%29%5E2\".........(2)....plug in \"x2=+-1.45\"and\"y2+=+2.1025\"\r
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\n" ); document.write( "\n" ); document.write( "\"2.1025+=+%28-1.45%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"2.1025+=+2.1025\"
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