Question

how do I know where which choices below go into the correct blanks?

Answer 1

In a 30-60-90 special right triangle, we have the following.

If the short leg is 7 cm, then x = 7.

So, the hypotenuse would be

$h=2x=2(7)=14\operatorname{cm}$

The length of the long leg is

$x\sqrt[]{3}=7\sqrt[]{3}\approx12.12\operatorname{cm}$

Therefore, the hypotenuse is 14 cm, and the long leg is 12.12 cm, approximately.