How do simplify (7+x)+7x ?

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Answer 1 · 2018-02-20T21:53:47

Use the fact that addition is associative.

#(7+x) + 7x = 7+(x+7x) = 7+8x#

Answer 2 · 2018-02-20T22:00:34

#7+8x#

#(7+x)+7x#

Because we have addition, rather then subtraction, we can just drop the parenthesis:

#7+x+7x#

If we treat #x# like #1x# it will be easier to see what we are doing:

#7+x+7x#

=

#7+1x+7x#

Now we just add #1x# and #7x#:

#7+1x+7x#

=

#7+8x#

#7# and #8x# are like apples and oranges, completely different, so you can add them.

This is our final answer:

#7+8x#