Respuesta :

Answer: About 3.06

Step-by-step explanation:

  We can use trigonometry functions to solve for AC. Let the ?, representing AC, be "x" in our mathematical work.

  Since we have the hypotenuse and x is adjacent to the angle given, I am going to use cosine.

      cos(θ) = [tex]\frac{adjacent}{hypotenuse }[/tex]

      cos(40) = [tex]\frac{x}{4}[/tex]

      0.766 ≈ [tex]\frac{x}{4}[/tex]

      3.06 ≈ x

      x ≈ 3.06