Math (trig)
posted by Kate on .
4cos(x)+5=6sec(x)

What about it? Are we solving for x ??
if so, then ....
4 cosx + 5 = 6/cosx
4cos^2x + 5cosx = 6
4cos^2x + 5cosx  6 = 0
(4cosx  3)(cosx + 2) = 0
cosx = 3/4 or cosx = 2 , Not possible since cosx ≤1
so cosx = 3/4
x = 41.4° or x = 221.4°