Two Practice Exam Trig Questions I Can't Finish

[stark lance]

using pythagorean identity [sin(θ)]² + [cos(θ)]² = 1

clear sin and cos squaring both
[sin(θ)]² = (x/4)²
[cos(θ)]² = [(y+2)/2]²

and remplace in the identity

(x/4)² + [(y+2)/2]² = 1