Solve equation 0 is less than equal to theta less than 360 -4+ cosine theta equals -8+ square root 3÷2

I guess you mean for 0 ≤ θ ≤ 360

-4+cosθ = -8 + √3/2
cosθ = -4 + √3/2
no solutions, since cosθ ≥ -1

so maybe you want to fix it, and this time use real math, instead of those annoying words? you can copy/paste the special characters from here.