Select from the drop-down menus to correctly identify whether the given operation is closed or not
closed with respect to each set of numbers,
real numbers are closed/not closed under addition
under addition
integers are closed/not closed under division
under division.
irrational numbers are closed/ not closed under multiplication
rational numbers are closed/not closed
under subtraction.

just sum

10 + 10 = 20

a)(x-2)^2+(y-1)^2=9

step-by-step explanation:

(picture explains)

step-by-step explanation:

this can be solved first with pythagorean theorem, which tells us to square both legs of the triangle and sum it. this will be equal to the square of the hypotenuse.

the hypotenuse is the side "opposite" the 90 degree angle, which is x.

so we can write using pythagorean theorem,

simplifying:

to further simplify this radical, we need to use the property  

thus