Answer:
k=6
Step-by-step explanation:
As stated, x=2/3, so you need to eval in the whole expression given
[tex]k*x^{2} -x-2=0[/tex]
which becomes the following>
[tex]k*(\frac{2}{3}) ^{2}-\frac{2}{3} -2=0\\[/tex]
Solving for K gives>
[tex]k=(2+\frac{2}{3})*\frac{9}{4}\\k=(\frac{9}{2} +\frac{3}{2})[/tex]
[tex]k=\frac{12}{2}[/tex]