document.write( "Question 230938: Find the indicated composition.\r
\n" ); document.write( "\n" ); document.write( " $\"f%28x%29=17x%5E2-6x\"$
\n" ); document.write( " $\"g%28x%29=8x-5\"$ \r
\n" ); document.write( "\n" ); document.write( "(f*g)(8) \n" ); document.write( "

Algebra.Com's Answer #171011 by likaaka(51) $\"\"$ $\"About$

You can put this solution on YOUR website!
First evaluate (f*g)(x), then substitute in x=8\r
\n" ); document.write( "\n" ); document.write( "Given $\"f%28x%29=17x%5E2-6x\"$ and $\"g%28x%29=8x-5\"$ , then (f*g)(x)= $\"%2817x%5E2-6x%29%288x-5%29\"$
\n" ); document.write( "Perform FOIL
\n" ); document.write( "(f*g)(x)= $\"%2817x%5E2%29%288x%29+%2B+%2817x%5E2%29%28-5%29+%2B+%28-6x%29%288x%29+%2B+%28-6x%29%28-5%29\"$
\n" ); document.write( "(f*g)(x)= $\"136x%5E3-85x%5E2-28x%5E2%2B30x\"$
\n" ); document.write( "(f*g)(x)= $\"135x%5E3-113x%5E2%2B30x\"$
\n" ); document.write( "Now substitute in x=8
\n" ); document.write( "(f*g)(8)= $\"135%288%5E3%29-113%288%5E2%29%2B30%288%29\"$
\n" ); document.write( "(f*g)(8)=135(512)-113(64)+30(8)
\n" ); document.write( "(f*g)(8)=69120-7232+240
\n" ); document.write( "(f*g)(8)=62136 \n" ); document.write( "

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