document.write( "Question 72616: please help me solve h(f(6))\r
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\n" ); document.write( "h(x)= -x^2 + 6x
\n" ); document.write( "f(x)= 7x - 40
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Algebra.Com's Answer #51915 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
First of all find f(6) by going to the original definition for f(x) and then replacing every
\n" ); document.write( "x by 6 and then simplifying the result.
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\n" ); document.write( "You were given that
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\n" ); document.write( "f(x) = 7*x - 40
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\n" ); document.write( "Then to find f(6) you replace every x in the equation for f(x) by 6 to get:
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\n" ); document.write( "f(6) = 7*6 - 40
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\n" ); document.write( "And you simplify the right side to get:
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\n" ); document.write( "f(6) = 42 - 40 = 2
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\n" ); document.write( "So now you know that f(6) = 2
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\n" ); document.write( "Next you are asked to find h(f(6)) given that
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\n" ); document.write( "\"h%28x%29+=+-x%5E2+%2B+6x\"
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\n" ); document.write( "To find h(f(6)) you just replace every x in h(x) with f(6). The result would be:
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\n" ); document.write( "\"h%28f%286%29%29+=+-%28f%286%29%29%5E2+%2B+6%2A%28f%286%29%29\"
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\n" ); document.write( "But on the right side you can substitute for f(6) its value which we found to be +2. If
\n" ); document.write( "you do your equation becomes:
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\n" ); document.write( "\"h%28f%286%29%29+=+-%282%29%5E2+%2B+6%2A2\"
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\n" ); document.write( "and the right side simplifies to:
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\n" ); document.write( "\"h%28f%286%29%29+=+-4+%2B+12+=+8\"
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\n" ); document.write( "So the answer to your problem is:
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\n" ); document.write( "\"h%28f%286%29%29+=+8\"
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\n" ); document.write( "Hope this helps you to better understand the way to work problems such as these.
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