Question

How do you solve `5sec(theta)+6=0`?

Answer 1

If `5sec(theta) + 6 = 0`
`color(white)("XXXX")` `sec(theta) = -6/5`
and
`color(white)("XXXX")` `cos(theta) = -5/6`

`theta = arccos(cos(theta))`

`rArr` `color(white)("XXXX")` `theta =arccos(-5/6)`

Using my trusty calculator:
`color(white)("XXXX")` `theta = 2.556 " radians"`