$\displaystyle \cos\alpha= \frac{576}{625}$\displaystyle \cos\alpha= \frac{576}{625}

$\displaystyle \cos\alpha= \frac{24}{25}$\displaystyle \cos\alpha= \frac{24}{25}

$\displaystyle \cos\alpha=-\sqrt{ \frac{24}{25} }$\displaystyle \cos\alpha=-\sqrt{ \frac{24}{25} }

$\displaystyle \cos\alpha= \frac{18}{25}$\displaystyle \cos\alpha= \frac{18}{25}