Question 973581
Slope from one side to the other is 20 meters at 20 degrees.

You want the sine of 20 degrees.  That is opposite (the vertical change)/hypotenuse, the land itself.  

sin(20)=x/20
20* sin (20)= vertical height
height is 6.84 meters. 

This makes sense.  At 30 degrees, the sine would be (1/2), and the vertical height 10 m.