document.write( "Question 1200522: Find a formula for the exponential function passing through the points (−3,5/27) and (2,45)
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Algebra.Com's Answer #834683 by greenestamps(13203)\"\" \"About 
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\n" ); document.write( "An exponential function is of the form \"y=ab%5Ex\".

\n" ); document.write( "Plug in the given (x,y) values to get two equations in a and b:

\n" ); document.write( "\"ab%5E%28-3%29=5%2F27\"
\n" ); document.write( "\"ab%5E2=45\"

\n" ); document.write( "Divide the second equation by the first.

\n" ); document.write( "\"%28ab%5E2%29%2F%28ab%5E%28-3%29%29=45%2F%285%2F27%29=45%2A%2827%2F5%29=9%2A27=243\"
\n" ); document.write( "\"b%5E5=243=3%5E5\"
\n" ); document.write( "\"b=3\"

\n" ); document.write( "Substitute b=5 in either original equation to find a.

\n" ); document.write( "\"a%283%5E2%29=45\"
\n" ); document.write( "\"9a=45\"
\n" ); document.write( "\"a=5\"

\n" ); document.write( "ANSWER: \"y=5%283%5Ex%29\"

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