In a 30-60-90 triangle the side opposite the 30 degree angle is half the length of the hypotenuse.
XZ = XY/2 = 4/2 = 2
By the Pythagorean theorem:
YZ = √(4² - 1²) = √(16-4) = √12 = 2√3
The tangent of an angle is the ratio of the length of the opposite side to the length of the adjacent side:
tan(Y) = XZ/YZ =2/2√3 = 1/√3 = √3/3
Answer is B. √3/3
