This is a 30°-60°90° triangle, such that the ratio of the side lengths are [tex]1: \sqrt{3}:2[/tex]. If the length of the hypotenuse is 14, then the length of [tex]x[/tex] is 7 units and [tex]y[/tex] is [tex]7 \sqrt{3} [/tex].
If you've never seen a 30°-60°90° triangle before, you can easily derive it by making an equilateral triangle (that is, with all angles of 60°) that has side lengths two. Then, you cut the triangle in half and solve for the hypotenuse using the Pythagorean Theorem.
