document.write( "Question 258234: How do I solve this problem f(x) = -0.3x^2 + 25x + 16 using the quadratic formula and graphing...I'm lost. I know x = 1 if this helps. \n" ); document.write( "
Algebra.Com's Answer #190078 by richwmiller(17219)\"\" \"About 
You can put this solution on YOUR website!
No x does not equal 1\r
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"-0.3x%5E2%2B25x%2B16+=+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=%2825%29%5E2-4%2A-0.3%2A16=644.2\".
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\n" ); document.write( " Discriminant d=644.2 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-25%2B-sqrt%28+644.2+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%2825%29%2Bsqrt%28+644.2+%29%29%2F2%5C-0.3+=+-0.635158878390421\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%2825%29-sqrt%28+644.2+%29%29%2F2%5C-0.3+=+83.9684922117238\"
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\n" ); document.write( " Quadratic expression \"-0.3x%5E2%2B25x%2B16\" can be factored:
\n" ); document.write( " \"-0.3x%5E2%2B25x%2B16+=+-0.3%28x--0.635158878390421%29%2A%28x-83.9684922117238%29\"
\n" ); document.write( " Again, the answer is: -0.635158878390421, 83.9684922117238.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+-0.3%2Ax%5E2%2B25%2Ax%2B16+%29\"
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