Step-by-step explanation:
Divide both sides by cosine to get:
[tex] - 4tan(x) = 5[/tex]
Divide both sides by -4 to get:
[tex]tan(x) = - \frac{5}{4} [/tex]
Take the arctangent of both sides to get:
[tex]x = arctan( - \frac{5}{4} )[/tex]
Plus any integer rotation of pi (180 degrees)
