What is the value of k in the function f(x) = 2-k / 5x+k if the graph of the function passes through the point (-1, 1/2)?
Thank you.
What is the value of k in the function f(x)?
Hello Julia!
\(f(x) = 2-k / 5\cdot x+k\\ so\\ f(x)=-\frac{k}{5}x+k+2\)
\(-\frac{k}{5}x= -\frac{k}{5}x(x+1)+\frac{k}{5} \)
\(f(x)= -\frac{k}{5}x(x+1)+\frac{k}{5}+k+2\\\color{blue} f(x)= -\frac{k}{5}x(x+1)+\frac{6}{5}k+2\)
\(\frac{6}{5}k+2=\frac{1}{2}\\ \frac{6}{5}k=-\frac{3}{2}\\ k=-\frac{3\cdot 5}{2\cdot 6}\\ \color{blue}k=-\frac{5}{4}\)
\(f(x)=2+\frac{5}{4\cdot 5}\cdot(-1)-\frac{5}{4}\\ {\color{blue}\frac{1}{2}}=2+\frac{5}{4\cdot 5}\cdot ({\color{blue}-1})-\frac{5}{4}\color{blue}\)
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