The inverse of f(x)= k(-x^3 -4x -9) is a function and f^-1(7)=1. What is the value of k?(adsbygoogle = window.adsbygoogle || []).push({});

Work is a picture: http://tinypic.com/view.php?pic=29xj4i8&s=5

Mod note: Too large picture deleted

Final Answer: k= (4y+10)/-7

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# Homework Help: Algebra II Honors Homework Help

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