In the following example of "Simplifying an Expression", what reason would be used for step D?

Simplify the expression 3k + 7 + 2k and justify each step

3k + 7 + 2k = 3k + 2k + 7 A
= (3k + 2k) + 7 B
= (3 + 2)k + 7 C
= 5k + 7 D
A. Addition
B. Commutative Property
C. Associative Property
D. Distributive Property
@Mathematics

Question

In the following example of "Simplifying an Expression", what reason would be used for step D?

Simplify the expression 3k + 7 + 2k and justify each step

3k + 7 + 2k = 3k + 2k + 7         A
                    = (3k + 2k) + 7      B
                    = (3 + 2)k + 7        C
                    = 5k + 7                 D
	A.	Addition
	B.	Commutative Property
	C.	Associative Property
	D.	Distributive Property
 @Mathematics

anonymous · Answer

That looks like plain ol' addition to me.
(3 + 2) = 5

asnaseer · Answer

yup - its addition

stormfire1 · Answer

I'd say it's addition (5+2) and distributive since you distributed the k afterwards :)

stormfire1 · Answer

eer...that shoulda been 3 + 2 :)