document.write( "Question 201620: Solve equation with quadratic formula
\n" ); document.write( "3n^2-15=-4n
\n" ); document.write( "

Algebra.Com's Answer #151818 by jsmallt9(3758)\"\" \"About 
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To use the quadratic formula we must first get the equation into the form:
\n" ); document.write( "\"ax%5E2+%2B+bx+%2B+c+=+0\"
\n" ); document.write( "This means:
  1. Get one side equal to zero
  2. Use the Commutative property of addition to rearrange the non-zero side in order from highest exponent to lowest.

\n" ); document.write( "Using these steps on your equation: \"3n%5E2+-+15+=+-4n\"
\n" ); document.write( "1. Make one side zero. By adding 4n to both sides the right side will become zero:
\n" ); document.write( "\"3n%5E2+-+15+%2B+4n+=+0\"
\n" ); document.write( "2. Change subtractions to additions
\n" ); document.write( "\"3n%5E2+%2B+%28-15%29+%2B+4n+=+0\"
\n" ); document.write( "3. Rearrange
\n" ); document.write( "\"3n%5E2+%2B+4n+%2B+%28-15%29+=+0\"

\n" ); document.write( "Now we have the equation in the proper form for the quadratic formula:
\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28b%5E2+-+4ac%29%29%2F2a\"
\n" ); document.write( "Looking at your rearranged equation we should be able to tell that
\n" ); document.write( "a = 3
\n" ); document.write( "b = 4
\n" ); document.write( "c = -15
\n" ); document.write( "Substituting these into the appropriate places in the formula we get:
\n" ); document.write( "\"x+=+%28+-%284%29+%2B-+sqrt%28%284%29%5E2+-+4%283%29%28-15%29%29%29%2F2%283%29\"
\n" ); document.write( "Squaring the 4
\n" ); document.write( "\"x+=+%28+-4+%2B-+sqrt%2816+-+4%283%29%28-15%29%29%29%2F2%283%29\"
\n" ); document.write( "Multiplying
\n" ); document.write( "\"x+=+%28+-4+%2B-+sqrt%2816+-+%28-180%29%29%29%2F6\"
\n" ); document.write( "Simplifying inside the square root
\n" ); document.write( "\"x+=+%28+-4+%2B-+sqrt%28196%29%29%2F6\"
\n" ); document.write( "\"sqrt%28196%29+=+14\" Substituting we get
\n" ); document.write( "\"x+=+%28-4+%2B-+14%29%2F6\"
\n" ); document.write( "Splitting the +- we get
\n" ); document.write( "\"x+=+%28-4+%2B+14%29%2F6\" or \"x+=+%28-4+-+14%29%2F6\"
\n" ); document.write( "Simplifying each:
\n" ); document.write( "\"x+=+10%2F6+=+1%264%2F6+=+1%262%2F3\" or \"x+=+-18%2F6+=+-3\"
\n" ); document.write( "The solutions:
\n" ); document.write( "\"x+=+1%262%2F3\" or \"x+=+-3\"
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