Final answer:
To find the value of y when cos64° = y/8, we calculate cos64° and then multiply it by 8. The calculated value of y ≈ 3.51.
The correct answer is D.
Step-by-step explanation:
The question asks us to find the value of y when cos64° = y/8. To do this, we first need to calculate the cosine of 64 degrees using a calculator or a trigonometric table. Once we have the value of cos64°, we multiply it by 8 to find the value of y.
cos64° ≈ 0.4384 (value from a trigonometric table or calculator)
Multiplying cos64° by 8 gives us: 0.4384 × 8 = 3.53.
Therefore, y ≈ 3.53, which is not listed in the supplied options, indicating there may have been an error in the question or the provided answer choices.