I was on here practicing the quadratic formula, hit the hint button, and in the midst of solving this problem it read 8 plus or minus the square root of 88 over 2. So the next hint added a 2 after the 8 and replaced the 88 with 22. So in then read 8 plus or minus two, the square root of 22. It confused me because I don't understand why the two was put there and the square root of 88 isn't 22.
They have simplified the square root. Here are the missing details:
sqrt(88)=sqrt(4x22)=sqrt(4)sqrt(22)=2sqrt(22). You can do this because the square root is really an exponent (it's the 1/2 power), so the square root will distribute across multiplication or division for the same reason integer exponents do.
Here's a KA practice exercise for that skill: https://www.khanacademy.org/math/algebra-basics/core-algebra-foundations/square-roots-for-college/e/simplifying_radicals
Or watch the video called "Simplifying radicals" for more info.
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