document.write( "Question 886820: Let f(x) = x2 - 8x + 5. Find f(-1) \n" ); document.write( "

Algebra.Com's Answer #536178 by josgarithmetic(39620) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let's say you want $\"y=f%5E-1%28x%29\"$ . Solve for y in $\"y%5E2-8y%2B5=x\"$ . You may need to complete the square for y to do it.\r
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\n" ); document.write( "\n" ); document.write( " $\"y%5E2-8y%2B16-16%2B5=x%2B16\"$ , the 16 completes the missing square
\n" ); document.write( " $\"%28y-4%29%5E2-16%2B5=x%2B16\"$
\n" ); document.write( " $\"%28y-4%29%5E2-11=x%2B16\"$
\n" ); document.write( " $\"%28y-4%29%5E2=x%2B16%2B11\"$
\n" ); document.write( " $\"%28y-4%29%5E2=x%2B27\"$
\n" ); document.write( " $\"y-4=0%2B-+sqrt%28x%2B27%29\"$
\n" ); document.write( " $\"highlight%28y=4%2B-+sqrt%28x%2B27%29%29\"$ \n" ); document.write( "

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