document.write( "Question 287740: Find A and k if the general equation is y=Ae^kx given two points (-2,-10) and (-1,-4). correct to two decimal places. \n" ); document.write( "

Algebra.Com's Answer #208520 by josmiceli(19441) $\"\"$ $\"About$

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$\"y+=+A%2Ae%5E%28kx%29\"$
\n" ); document.write( "(-2,-10)
\n" ); document.write( "(1) $\"-10+=+A%2Ae%5E%28k%2A%28-2%29%29\"$
\n" ); document.write( "(-1,-4)
\n" ); document.write( "(2) $\"-4+=+A%2Ae%5E%28k%2A%28-1%29%29\"$
\n" ); document.write( "Solve both equations for $\"A\"$
\n" ); document.write( "(1) $\"A+=+-10%2Ae%5E%282k%29\"$
\n" ); document.write( "(2) $\"A+=+-4%2Ae%5Ek\"$
\n" ); document.write( "so,
\n" ); document.write( " $\"-10%2Ae%5E%282k%29+=+-4%2Ae%5Ek\"$
\n" ); document.write( " $\"e%5E%282k%29%2Fe%5Ek+=+2%2F5\"$
\n" ); document.write( " $\"%28e%5Ek%29%5E2%2Fe%5Ek+=+2%2F5\"$
\n" ); document.write( " $\"e%5Ek+=+2%2F5\"$
\n" ); document.write( " $\"k+=+ln%28.4%29\"$
\n" ); document.write( " $\"k+=+-.92\"$
\n" ); document.write( "and
\n" ); document.write( "(2) $\"A+=+-4%2Ae%5Ek\"$
\n" ); document.write( " $\"A+=+-4%2Ae%5E%28-.92%29\"$
\n" ); document.write( " $\"A+=+-4%2A.4\"$
\n" ); document.write( " $\"A+=+-1.6\"$ \n" ); document.write( "

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