Are perfect squares closed under subtraction

  no

Step-by-step explanation:

The set of perfect squares includes {0, 1, 4, 9, 16, 25, ...}.

Subtracting a couple of the elements, we get ...

  4 - 1 = 3 . . . . not a member of the set

The set is NOT CLOSED under subtraction.

10x

step-by-step explanation:

the greatest common factor 30 and 20 is 10

5 is a common factor of 30 and 20 but 10 is also a factor and 10 is greater than 5 so 5 will definitely not be apart of our answer

now the most amount of x's you factor our is just 1 factor of 1

so 10x the gcf of the terms in the polynomial

x=6 and x=3

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