Cos is -4/3 not 5/5 solve properly you are wasting my trials

The value of cosine for any angle must be between $-1$ and 1, inclusive.

$$-1 \le \cos \theta \le 1$$

If $\cos B = -\frac{4}{3}$, this value is approximately $-1.333...$, which is less than $-1$.
Therefore, $\cos B = -\frac{4}{3}$ is not a possible value for the cosine of any angle.

Please double-check the problem statement for the value of $\cos B$. The original problem stated $\cos B = -\frac{4}{5}$, which is a valid value.

Let me know if you have the correct value for $\cos B$ or if you'd like to proceed with the original value of $\cos B = -\frac{4}{5}$.