Question

Diego is planning to make a wooden cookbook stand for his mom. The depth of the stand will be 10 inches, and it will hold a cookbook at a 40° angle. Which equation can be used to find x, the length of the slanted side?

A. sin(40°) = 10 in
B. cos(40°) = 10 in
C. tan(40°) = 10 in
D. cos(40°) = 10 in

Answer 1

To find the slanted side length x, we use the cosine function because the depth is the side adjacent to the angle. Therefore, the correct equation is cos(40°) = 10/x.

The correct answer is B.

Step-by-step explanation:

To find the length of the slanted side x of the wooden cookbook stand that Diego is planning to make, which will hold a cookbook at a 40° angle with a depth of 10 inches, we need to use trigonometric functions.

The depth corresponds to the side adjacent to the 40° angle, so we need an equation that relates the adjacent side to the hypotenuse. The correct equation to use is cos(40°) = rac{10 ext{ in}}{x}.