Final answer:
To determine the measure of ∠B in a right triangle with sides AB = 6, AC = 3, and BC = 3√5, we use the cosine function. The correct equation is cos m∠B = √5 / 5, derived from the trigonometric ratio that relates the adjacent side to the hypotenuse.
Step-by-step explanation:
To find the measure of ∠B in triangle ABC, we can use trigonometric functions that relate the sides of the triangle to its angles. Since triangle ABC is a right triangle with AB = 6, AC = 3, and BC = 3√5 (the hypotenuse), we can use the Pythagorean theorem and trigonometric ratios derived from it.
Using the given side lengths, we can determine the cosine and sine of ∠B. The cosine of an angle in a right triangle is the adjacent side divided by the hypotenuse, and the sine of an angle is the opposite side divided by the hypotenuse. Thus, for ∠B:
cos m∠B = AB / BC = 6 / (3√5) = √5 / 5
Therefore, the correct equation to find the measure of ∠B is:
cos m∠B = √5 / 5