This is a 30-60-90 triangle.
What is the measure of x?
13
Х
X =
= [?]

Answer:
[tex]x=3[/tex]
Step-by-step explanation:
We know that in a 30-60-90 triangle, if the side opposite the 30 degree angle is [tex]x[/tex], then the side opposite the 30 degree angle is [tex]x\sqrt{3}[/tex] and the side opposite the 90 degree angle is [tex]2x[/tex].
We know that, in this diagram, [tex]x[/tex] is opposite the 60 degree angle because it "looks" bigger(by inspection).
So, [tex]x=\sqrt{3}\cdot \sqrt{3}=(\sqrt{3})^2=3[/tex].
Therefore, the answer is [tex]\boxed{x=3}[/tex] and we're done!