## what am i doing wrong? 2n - 3(4n + 5) = -6(n - 3) - 1

Simplificatation, evaluation, linear equations, linear graphs, linear inequalities, basic word problems, etc.
infinite_product
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### what am i doing wrong? 2n - 3(4n + 5) = -6(n - 3) - 1

okay, i am an eighth grader taking algebra 1 and so far its been a breeze. but now we're solving equations with variables on both ends and i am sorta lost. i say sorta because i get it and understand what to do (combine like terms, opposite operations, ...the works...) but then i get to solving the problem and i do everything how the book and my teacher says, but the answers just don't end up working out when i plug my answers in for the variables...

heres one of my problems:

what is the solution of 2n - 3(4n + 5) = -6(n - 3) - 1 ?

i did this:

distributed, so i rewrote the problem as: 2n - 12n + 15 = -6n - -18 - 1
then i combined like terms: 2n + -12n + 6n = -15 + 18 + -1 and got: -4n = 2
then i divide each side by -4 to isolate the variable and 2 / -4 is - 1/2

according to my teacher, the answer is -8. no matter how many times i rework this problem, i still get negative one half.....

can someone please tell me what i am doing wrong here?

stapel_eliz
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Joined: Mon Dec 08, 2008 4:22 pm
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what is the solution of 2n - 3(4n + 5) = -6(n - 3) - 1 ?

i did this:

distributed, so i rewrote the problem as: 2n - 12n + 15 = -6n - -18 - 1
How are you getting that -3(+5) equals +15 instead of -15?

Simplifying with Parentheses

infinite_product
Posts: 2
Joined: Thu Sep 29, 2011 1:53 am
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### Re: what am i doing wrong? 2n - 3(4n + 5) = -6(n - 3) - 1

hmm... i think i was thinking negative three.......... thanks.....