How do you simplify the square root of 4? It's simple. What times itself equals 4? The answer would be 2! And because its √4×√4 it is simplified into 2×2=4
For number 2 the same thing applies. What times itself equals 12?
This one is a little tricky because it is not a perfect square (like how √4 is.)
But the square root of 12 is 3.46, which we can round to about 3.5.
Now what is the square root of 6? Once agian it is not a perfect root so the answer will be a decimal. 2.44 or rounded to 2.45.
Now what is 3.5 × 2.45? Answer is the answer is about 8.57 or rounded 8.60.
For the third question what is the square root of 7? The answer would be about 2.65. Remember PEMDAS. Parenthesis, exponents, multiply, divide, add, subtract. (yeah you know this:) First comes parenthesis. SO 1 minus 2.65 is equal to - 1.65. Next set of parenthesis is 1+ the square √7 so it would be the opposite of what we just did. So 1 plus 2.65. That equals 3.65.
Now when there are 2 sets of parenthesis next to eachother )( That means we need to MULTIPLY the two sides. So -1.65 × 3.65 ≈ - 6.
Last but not least Number 30. It might look scary but its not.
What is the square root of 2? Its about 1.5. The fraction is just another form for this 3÷1.5 The answer is 2.
Hope this was Helpful, sorry it was a little long but you needed an explanation :)