The value of x is:
To solvbe this, we need to use the tan function. The 60º is at the top left of the triangle, and the 30º angle is on the bottom right.
Then we know, the angle bottom right = 30º, the opposite leg = x and the adjacent leg = 12
The trignometrical function that relates those 3 things is tangent:
In this case:
Thus:
Now we need to rationalize the answer. To do it, we multiply and divide by the denominator:
And that's the answer