In general call the shortest side a and remember this is always the side opposite the 30 degree angle. Then the other leg/side has length a(square root 3) and the hypotenuse has length 2a.
So in the case of a=7, the hypotenuse has length 14.
If the shortest leg of a 30-60-90 triangle has length 12, the length of the hypotenuse is: 24
Hypotenuse = 24
The hypotenuse is 30.
30
24
22
6
22
6
14 units
You need the length of a side. Try sketching different size triangles with 30/60/90 degree angles - there's an infinite number of them. The length of the hypotenuse is the shortest side / sin30 or the third side / sin60. As sin 30 is 0.5 then the hypotenuse is twice the length of the shortest side (or the third side divided by ½root3 ).
30 units.