Do you remember what the sine of an angle is ? If the angle is in a right triangle, then the sine of the angle is (the opposite side) divided by (the hypotenuse). So in this triangle, sin(38) = 24/x . And. X = 24/sin(38) . You can find sin(38) with your calculator or on line, and once you have that number, you're just a simple division away from knowing 'x'.