document.write( "Question 525050: Please help me get this!!
\n" ); document.write( "Find the exponential function f(x)=ab^x that goes through (0,9) & (4,25)
\n" ); document.write( "Please show me the steps, so I can learn!!
\n" ); document.write( "Thanks so much :-)
\n" ); document.write( "

Algebra.Com's Answer #348002 by solver91311(24713)\"\" \"About 
You can put this solution on YOUR website!
\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "You are panicking for no reason. This is a LOT easier than it looks.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "If a point is on a function, then the value of the function must be the coordinate when the coordinate is substituted for .\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "The first point is so the value of the function must be 9 if the value of is 0.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "But anything raised to the zero power is 1, therefore:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Plugging that value back into the function we have:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Then, given that is on the curve, we can say:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "A little Algebra Music, Maestro:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Take the positive 4th root of the RHS (the base of an exponetial has to be greater than zero and not equal to 1)\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "John
\n" ); document.write( "
\n" ); document.write( "My calculator said it, I believe it, that settles it
\n" ); document.write( "
\"The

\n" ); document.write( "
\n" ); document.write( "
\n" );