How do you solve #-3( 3- 2n ) + 7n = 3( n + 3)#?

2 Answers
Mar 15, 2018

Answer:

#n=1.8#

Explanation:

#-9+6n+7n=3n+9#

#-9+13n=3n+9#

#-18=-10n#

#n=1.8#

Mar 15, 2018

Answer:

Re-arrange and reduce to find #n=1.8#

Explanation:

First, add #3(3-2n)# to both sides. This eliminates the #-3(3-2n)# from the Left-Hand Side (LHS)

#7n=3(n+3)+3(3-2n)#

Since both sets of parentheses have the same coefficient, you can add the contents of the parentheses together without expanding:

#7n=3(n+3+3-2n) rArr 7n=3(6-n)#

NOW we expand the parentheses, and move all of the #n#'s to the LHS:

#7n=18-3n rArr 10n=18#

Finally, we divid through by #n#'s coefficient to find the value of #n#:

#n=18/10=1.8#