document.write( "Question 113993: Solve the quadratic equation using the Quadratic Formula:
\n" ); document.write( "3x^2-2x-2=0
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "

Algebra.Com's Answer #82951 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Starting with the general quadratic\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"ax%5E2%2Bbx%2Bc=0\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "the general solution using the quadratic equation is:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So lets solve \"3%2Ax%5E2-2%2Ax-2=0\" ( notice \"a=3\", \"b=-2\", and \"c=-2\")\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"x+=+%28--2+%2B-+sqrt%28+%28-2%29%5E2-4%2A3%2A-2+%29%29%2F%282%2A3%29\" Plug in a=3, b=-2, and c=-2\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+%28-2%29%5E2-4%2A3%2A-2+%29%29%2F%282%2A3%29\" Negate -2 to get 2\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+4-4%2A3%2A-2+%29%29%2F%282%2A3%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\".)\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+4%2B24+%29%29%2F%282%2A3%29\" Multiply \"-4%2A-2%2A3\" to get \"24\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+sqrt%28+28+%29%29%2F%282%2A3%29\" Combine like terms in the radicand (everything under the square root)\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+2%2Asqrt%287%29%29%2F%282%2A3%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B-+2%2Asqrt%287%29%29%2F6\" Multiply 2 and 3 to get 6\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So now the expression breaks down into two parts\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"x+=+%282+%2B+2%2Asqrt%287%29%29%2F6\" or \"x+=+%282+-+2%2Asqrt%287%29%29%2F6\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Now break up the fraction\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"x=%2B2%2F6%2B2%2Asqrt%287%29%2F6\" or \"x=%2B2%2F6-2%2Asqrt%287%29%2F6\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Simplify\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"x=1+%2F+3%2Bsqrt%287%29%2F3\" or \"x=1+%2F+3-sqrt%287%29%2F3\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So these expressions approximate to\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"x=1.21525043702153\" or \"x=-0.548583770354864\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=1.21525043702153\" or \"x=-0.548583770354864\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Notice when we graph \"3%2Ax%5E2-2%2Ax-2\", we get:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "when we use the root finder feature on a calculator, we find that \"x=1.21525043702153\" and \"x=-0.548583770354864\".So this verifies our answer
\n" ); document.write( "
\n" ); document.write( "
\n" );