The value which is equivalent to sin 51° is cos 39°. The correct option is B) cos 39°
Complementary angle theorem
From the complementary angle theorem, we have that
The sine of an angle is equal to the cosine of its complementary angle
That is,
sin θ = cos (90° - θ)
Recall: Complementary angles sum up to 90°
Then, we can write that
sin 51° = cos (90° - 51°)
sin 51° = cos 39°
Hence, the value which is equivalent to sin 51° is cos 39°. The correct option is B) cos 39°
Learn more on Complementary angle theorem here: https://brainly.com/question/26546085
