You can put this solution on YOUR website! Tipped up at 30 degrees makes the bed the hypotenuse, and that is 12 feet.
The angle with the frame is 30 degrees
The height of the bed from the frame is the sine of 30 = x/12, where x is the height above the frame.
sin 30=(1/2)
The height above the frame is 6 feet.
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