The answer is the you need to know is 100
As long as your indexes are the same (which they are; they are all square roots) and you radicands are the same (which they are; they are all 11), then you can add or subtract. The rules for adding and subtracting radicals are more picky than multiplying or dividing. Just like adding fractions or combining like terms. Since all the square roots are the same we only have to worry about the numbers outside. In fact, it may help to factor out the sqrt 11:

. The numbers subtract to give you -9. Therefore, the simplification is
Answer:
2b
Step-by-step explanation:
Identify the greatest common factors of 2 and 6, the answer is 2
identify the greatest common between b^2 and b, the answer is b
ao therefore the greatest common factor is 2b.
9*10(9) is equal to 810, and 3*10(-4) is equal to -120. This is 6.75 times larger than -120.
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Hope this helps!
1/2 * 2/2 = 2/4 which is not 2/7
2/1 * 7/7 = 14/7 which is not 7/14
1/2 * 7/7 = 7/14 which is 7/14 yes
2/1 * 7/7 = 14/7 which is not 14/21 no
Choice C