A television antenna is on the roof of a building, the angle of elevation of the top and the button of the antenna are 51 degrees and 42 degrees respectively.How tall is the antenna?

From where is the angle of elevation measured? You need to provide at least one length in order to compute another length.

I assume "button" means "bottom"

To find the height of the antenna, we can use trigonometry. Let's call the height of the building H and the height of the antenna h.

First, we need to visualize the situation. Imagine a right triangle where the base represents the height of the building (H), the vertical side represents the height of the antenna (h), and the hypotenuse represents the distance from the antenna to the observer.

Given that the angle of elevation of the top of the antenna is 51 degrees and the angle of elevation of the bottom of the antenna is 42 degrees, we can see that the angle between the bottom of the antenna and the top is 51 - 42 = 9 degrees.

Now, we can use trigonometric ratios to calculate the height of the antenna.

Using the tangent function, tan(theta) = opposite/adjacent, we have:

tan(9 degrees) = h/H

Rearranging the equation to solve for h, we have:

h = tan(9 degrees) * H

Now, we need the value of H, which represents the height of the building. Unfortunately, it is not given in the question. Without this information, we cannot find the exact height of the antenna.

To continue, we would need the specific value of H in order to calculate the height of the antenna using the given angles of elevation.