You can solve this using trigonometry.
First we will use tan, for y, which is the opposite side in regards to the 60 degree angle.
We can write the following,
tan x= opposite / adjacent
tan 60= y / 3
y = tan 60 * 3
y = 5.19615
or just
y = 5.2
Now onto side x.
For this one, we can use cos.
We will write the following,
cos x = adjacent / hypothenuse
cos 60 = 3 / x
x = 3 / cos60
x = 6
