document.write( "Question 269456: Hi. I am completely lost about this problem. Can you please explain how you get the answer. Thanks in advance \r
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\n" ); document.write( "\n" ); document.write( "Find an equation of a rational function f that satisfies the conditions:
\n" ); document.write( "vertical asymptotes: x = - 1, x = 6
\n" ); document.write( "horizontal asymptote: y = 3
\n" ); document.write( "x-intercepts: - 7, 5
\n" ); document.write( "hole at x = 0
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Algebra.Com's Answer #197494 by drk(1908)\"\" \"About 
You can put this solution on YOUR website!
Lets go one step at a time.
\n" ); document.write( "vertical asymptotes: x = - 1, x = 6
\n" ); document.write( "we get a basic idea that our function is
\n" ); document.write( "(i) \"y+=+%28ax%2Bb%29%2F%28%28x%2B1%29%28x-6%29%29\"
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\n" ); document.write( "horizontal asymptote: y = 3
\n" ); document.write( "we know that as x approaches infinity, then the function approaches 3. SInce the denominator is degree 2, the numerator must be degree 2, so we could say
\n" ); document.write( "(ii) \"y+=+%283x%5E2%2B+ax%2Bb%29%2F%28%28x%2B1%29%28x-6%29%29\"
\n" ); document.write( "-----
\n" ); document.write( "x-intercepts: - 7, 5
\n" ); document.write( "If we let x = -7 or x = 5, then the function should become 0.
\n" ); document.write( "part 1 - x = -7 gets us
\n" ); document.write( "(iii) \"y+=+%283%28-7%29%5E2+-+7a+%2B+b%29%2F%28%28%28-7%29%2B1%29%28%28-7%29-6%29%29\"
\n" ); document.write( "which becomes
\n" ); document.write( "(iv) \"y+=+%28147+-+7a+%2B+b%29%2F78\"
\n" ); document.write( "this means that the numerator = 0, so
\n" ); document.write( "If a = 6, then b = -105. So our equation is now
\n" ); document.write( "(v) \"y+=+%283x%5E2%2B+6x+-+105%29%2F%28%28x%2B1%29%28x-6%29%29\"
\n" ); document.write( "part 2 - x = 5 gets us
\n" ); document.write( "(vi) \"y+=+%283%2A5%5E2%2B+5a+%2B+b%29%2F%28%285%2B1%29%285-6%29%29\"
\n" ); document.write( "which becomes
\n" ); document.write( "(vii) \"y+=+%2875%2B+5a+%2B+b%29%2F%28-6%29\"
\n" ); document.write( "this means that the numerator = 0, so
\n" ); document.write( "If a = 6, then b = -105. The key part is setting the numerator of (iv) = numerator of (vii) to get values for a and b that work
\n" ); document.write( "So, our new equation is
\n" ); document.write( "(viii) = \"y+=+%283x%5E2%2B+6x+-+105%29%2F%28%28x%2B1%29%28x-6%29%29\"
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\n" ); document.write( "hole at x = 0
\n" ); document.write( "this means that we multiply both numerator and denominator by x to get our final answer equation as
\n" ); document.write( "(ix) \"y+=+%28%28x%29%283x%5E2%2B+6x+-+105%29%29%2F%28%28x%29%28x%2B1%29%28x-6%29%29\"
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