document.write( "Question 475456: 3x² - 9x + 7 = 0 be? How many solutions would that mean?\r
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Algebra.Com's Answer #326035 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!

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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 \"3%2Ax%5E2-9%2Ax%2B7=0\" ( notice \"a=3\", \"b=-9\", and \"c=7\")
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\n" ); document.write( " \"x+=+%28--9+%2B-+sqrt%28+%28-9%29%5E2-4%2A3%2A7+%29%29%2F%282%2A3%29\" Plug in a=3, b=-9, and c=7
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\n" ); document.write( " \"x+=+%289+%2B-+sqrt%28+%28-9%29%5E2-4%2A3%2A7+%29%29%2F%282%2A3%29\" Negate -9 to get 9
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\n" ); document.write( " \"x+=+%289+%2B-+sqrt%28+81-4%2A3%2A7+%29%29%2F%282%2A3%29\" Square -9 to get 81 (note: remember when you square -9, you must square the negative as well. This is because \"%28-9%29%5E2=-9%2A-9=81\".)
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\n" ); document.write( " \"x+=+%289+%2B-+sqrt%28+81%2B-84+%29%29%2F%282%2A3%29\" Multiply \"-4%2A7%2A3\" to get \"-84\"
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\n" ); document.write( " \"x+=+%289+%2B-+sqrt%28+-3+%29%29%2F%282%2A3%29\" Combine like terms in the radicand (everything under the square root)
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\n" ); document.write( " \"x+=+%289+%2B-+i%2Asqrt%283%29%29%2F%282%2A3%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+=+%289+%2B-+i%2Asqrt%283%29%29%2F%286%29\" Multiply 2 and 3 to get 6
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\n" ); document.write( " After simplifying, the quadratic has roots of
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\n" ); document.write( " \"x=3%2F2%2Bsqrt%283%29%2F6%2Ai\" or \"x=3%2F2-sqrt%283%29%2F6%2Ai\"
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