Posted by ben on .
One of the angles of a right triangle measures 30°, and the hypotenuse is 10 inches long. How long is the side opposite the 30° angle?

math 
Reiny,
sin 30° = x/10
x = 10sin30° = 5
or
using the ratio of sides of the 306090 triangle
x/1 = 2/10
x = 5