I'm looking at the top at 79.9 angle. I'm 100ft away. What's the height of the building?

To solve this, notice that you have the angle component (I will call this a) and the x-component (the distance of you from the building) of a trig formula, and you are looking for the y-component. We will use the tangent formula, since this incorporates the angle, x, and y components.

1. Write the formula

tan (a) = y : x

2. Rewrite to include the known values.

tan (79.9) = y : 100

3. Solve for the unknown variable, y.

tan (79.9) * 100 = y : 100 * 100

tan (79.9) * 100 = y

4. A fancy step that I call the "flip flop."

y = tan (79.9) * 100

5. Use a calculator to find the value (make sure the calculator is in "degree" and not "radians" mode).

y = 561.3968

6. Round the number as is appropriate for this problem.

Have a great day!

So this is a trig problem

so you have a right triangle

base=100 ft

from wher you are standing, it is a 79.9 angle to the top

we want to find the height of the tower or the opposite side

the base is the adjacent side so you are looking for o/a or tan (79.9) since you know one of the sides so therefor

tan (79.9) = h/100

evaluate tan (79.9)

tan (79.9) = 5.61396

5.61396=h/100

multiply both sides by 100

561.396=h

round to tenths place

561.4

the height=561.4 ft