SOLUTION: -4(9-3y)+12y-14=9-33y+12y-14 =9-65y-14 =65y+23 Is this expression simplified correctly?

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Question 660050: -4(9-3y)+12y-14=9-33y+12y-14
=9-65y-14
=65y+23
Is this expression simplified correctly?
Answer by math-vortex(648) About Me  (Show Source):
You can put this solution on YOUR website!
Hi, there --

First, let me say that I REALLY appreciate when I student shows me what they've tried so far. 
Nice job!

There is a problem with your notation. You start in the problem statement with an equation. 
However, in the two steps you show of your work, you have the right side of the equation, but 
not the left.

Here's how I would do this problem. I assume that you are trying to simplify that complicated 
equation in the problem statement, getting it to something closer to a "y equals something" 
form.

-4%289-3y%29%2B12y-14=9-33y%2B12y-14

Multiply -4 across the terms inside the parentheses.
-36%2B12y%2B12y-14=9-33y%2B12y-14

Combine like terms on the left side: 12y+12y is 24y and  -36-14 is -50.
24y-50=9-33y%2B12y-14

Combine like terms on the right side: -33y+12y is -21y and 9-14 is -5.
24y-50=-21y-5

Add 21y to both sides. This isolates the y-terms on the left side of the equation.
45y-50=-5

Add 50 to both sides. This isolates the constant terms on the right side of the equation.
45y=45

Divide both sides of the equation by 45: 45y/45 is just y, and 45/45 is 1.
y=1

Check your work in the ORIGINAL equation.
-4%289-3y%29%2B12y-14=9-33y%2B12y-14
-4%289-3%281%29%29%2B12%281%29-14=9-33%281%29%2B12%281%29-14
-4%289-3%29%2B12-14=9-33%2B12-14
-4%286%29-2=-26
-26=-26
Check!

If this is unclear, or you still have questions, please email me.

Mrs.Figgy
math.in.the.vortex@gmail.com