document.write( "Question 1062497: solve 25^y + 3 (5^y) =3 \n" ); document.write( "
Algebra.Com's Answer #677405 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
25^y + 3 (5^y) =3
\n" ); document.write( "------
\n" ); document.write( "\"5%5E%282y%29+%2B+3%2A%285%5Ey%29+-+3+=+0\"
\n" ); document.write( "-----
\n" ); document.write( "Sub x for 5^y
\n" ); document.write( "---
\n" ); document.write( "\"x%5E2+%2B+3x+-+3+=+0\"
\n" ); document.write( "\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"1x%5E2%2B3x%2B-3+=+0\") has the following solutons:
\n" ); document.write( "
\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
\n" ); document.write( "
\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
\n" ); document.write( "
\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%283%29%5E2-4%2A1%2A-3=21\".
\n" ); document.write( "
\n" ); document.write( " Discriminant d=21 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-3%2B-sqrt%28+21+%29%29%2F2%5Ca\".
\n" ); document.write( "
\n" ); document.write( " \"x%5B1%5D+=+%28-%283%29%2Bsqrt%28+21+%29%29%2F2%5C1+=+0.79128784747792\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%283%29-sqrt%28+21+%29%29%2F2%5C1+=+-3.79128784747792\"
\n" ); document.write( "
\n" ); document.write( " Quadratic expression \"1x%5E2%2B3x%2B-3\" can be factored:
\n" ); document.write( " \"1x%5E2%2B3x%2B-3+=+%28x-0.79128784747792%29%2A%28x--3.79128784747792%29\"
\n" ); document.write( " Again, the answer is: 0.79128784747792, -3.79128784747792.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B3%2Ax%2B-3+%29\"

\n" ); document.write( "\n" ); document.write( "================
\n" ); document.write( "Ignore the negative value
\n" ); document.write( "---
\n" ); document.write( "x =~ 0.79129
\n" ); document.write( "5^y = 0.79129
\n" ); document.write( "y*log(5) = log(0.79129)
\n" ); document.write( "y = log(0.79129)/log(5)
\n" ); document.write( "y =~ -0.14545
\n" ); document.write( "
\n" );