Proving that $\mathbb{Q}_p$ is not formally real.

Question

I've been looking for a concrete proof without results. The only hint that I have found says:

1) $\mathbb{Q}_2$ contains a square root of $-7$.

2) $\mathbb{Q}_p$ ($p>2$) contains a square root of $1-p$.

Question 1: How to prove 1 and 2? if it is very long to write as an answer, is there any book or paper showing the proof?

Question 2: Is there any better way to prove that $\mathbb{Q}_p$ is not formally real?