Mark M. answered 06/11/20
Retired math prof. Very extensive Precalculus tutoring experience.
x = 4cosθ + 2 So, cosθ = (x-2) / 4
y = 2sinθ - 5 So, sinθ = (y+5) / 2
Since cos2θ + sin2θ = 1, we have (x-2)2 / 16 + (y+5)2 / 4 = 1
Since -1 ≤ cosθ ≤ 1, -4 ≤ 4cosθ ≤ 4. So, -2 ≤ 4cosθ + 2 ≤ 6. That is, x lies in the interval [-2,6].