Question

a 12 - foot ladder is placed 4 feet away from a house as shown. what is the value of x, rounded to the nearest degree? according to the manufacturer, if the angle the ladder forms with the ground, x, is between 70° and 75°, then it meets safety standards. is this ladder being used safely?

Explanation:

Step1: Use cosine function

$\cos(x)=\frac{4}{12}=\frac{1}{3}$

Step2: Find angle

$x = \cos^{-1}(\frac{1}{3})\approx70.53^{\circ}$

Answer:

$71^{\circ}$, Yes