Answer:
x ≈ 26.4
Step-by-step explanation:
Using the cosine ratio in the right triangle
cos47° = [tex]\frac{adjacent}{hypotenuse}[/tex] = [tex]\frac{CD}{AD}[/tex] = [tex]\frac{18}{x}[/tex] ( multiply both sides by x )
x × cos47° = 18 ( divide both sides by cos47° )
x = [tex]\frac{18}{cos47}[/tex] ≈ 26.4 ( to the nearest tenth )