Final answer:
The statement tan 40° = 0.84 helps in understanding similar right triangles, calculating sides of a 40°-50°-90° triangle, and finding the lengths of legs given one side. The tangential value is a ratio of the opposite side to the adjacent side in right triangles.
Step-by-step explanation:
Understanding the statement tan 40° = 0.84 involves recognizing the relationships in right triangles and the basic principles of trigonometry. The value 0.84 represents the ratio of the opposite side to the adjacent side of a right triangle where one of the angles is 40°.
- All right triangles with an acute angle of 40° are similar to each other. This is because they will all have the same angle ratios.
- Knowing that tan 40° = 0.84 is enough information to calculate the sides of any 40°-50°-90° triangle, given one side. Using the ratio and the Pythagorean theorem, all sides can be determined.
- If you know tan 40° = 0.84 and the length of the leg opposite to the 40° angle, then you can calculate the length of the adjacent leg. This is the practical use of the tangent function.
Answer choices 'a', 'c', and 'd' are all valid explanations of what it means when we say tan 40° = 0.84. However, choice 'b' is incorrect since it muddles the Pythagorean theorem, and 'e' incorrectly associates the tangent value with the ratio of the opposite side to the hypotenuse, when in fact, tangent relates to the opposite and adjacent sides.