Triangle XYZ has sides XY = 3", YZ = 4", and XZ = 5". If angle Y is a right angle, and side YZ is opposite angle X, what is the tan of angle X?
In triangle XYZ, angle X is opposite side YZ and angle Y is a right angle. Therefore, angle X is also a right angle.
Since the tan function is undefined for right angles, the tan of angle X in this triangle is undefined.