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Oct 21 2013 09:21am
-2x + 6y - 1 = 0

5x - 15y + 2.5 = 0

Solve each of the following systems using elimination

Please help me!
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Oct 21 2013 09:36am
Since you have to use elimination, you want to manipulate your 2 equations to have either your x or y to have equal but opposite values (one positive one negative). After that you will add your 2 equations together and have just one variable remaining. Solve for that variable, then plug that value back into one of your original 2 equations to solve for your other variable.

I would work through it, but I'm on my phone
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Oct 21 2013 10:27am
Quote (TritonV8 @ Oct 21 2013 08:36am)
Since you have to use elimination, you want to manipulate your 2 equations to have either your x or y to have equal but opposite values (one positive one negative). After that you will add your 2 equations together and have just one variable remaining. Solve for that variable, then plug that value back into one of your original 2 equations to solve for your other variable.

I would work through it, but I'm on my phone


Thank you
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Oct 21 2013 10:42pm
Quote (TritonV8 @ Oct 22 2013 01:36am)
Since you have to use elimination, you want to manipulate your 2 equations to have either your x or y to have equal but opposite values (one positive one negative). After that you will add your 2 equations together and have just one variable remaining. Solve for that variable, then plug that value back into one of your original 2 equations to solve for your other variable.

I would work through it, but I'm on my phone


Uh, did you even look at the equations?

@OP Pretty sure you can't solve this set of simultaneous linear equations in the normal sense, as they produce an infinite number of solutions.

The two equations are the exact same. That is, -2x + 6y - 1 ≡ 5x - 15y + 2.5.
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Oct 21 2013 10:47pm
Quote (canetoado @ Oct 21 2013 11:42pm)
Uh, did you even look at the equations?

@OP Pretty sure you can't solve this set of simultaneous linear equations in the normal sense, as they produce an infinite number of solutions.

The two equations are the exact same. That is, -2x + 6y - 1 ≡ 5x - 15y + 2.5.


Like I stated in my original post, I was on my phone and didn't work the problem. I just gave him the steps to use for solving the problem.
In the case where the answer comes out to be 0 = 0, this would imply that the answer is all real numbers. If the answer came out to be not equal (i.e. 7=5), this would imply there is no solution.
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Oct 22 2013 11:37am
Quote (GrafEmpire @ Oct 21 2013 05:21pm)
-2x + 6y - 1 = 0

5x - 15y + 2.5 = 0

Solve each of the following systems using elimination

Please help me!


if thats grade 10, i wonder what you guys do in grade 1

xD
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Oct 24 2013 09:58pm
Quote (GrafEmpire @ Oct 21 2013 10:21am)
-2x + 6y - 1 = 0

5x - 15y + 2.5 = 0

Solve each of the following systems using elimination

Please help me!



Technically they are not simultaneous equations because they are the same equation. If you multiply equation-1 by 2.5, you get equation-2.
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Oct 24 2013 10:07pm
Quote (Snyft @ Oct 22 2013 01:37pm)
if thats grade 10, i wonder what you guys do in grade 1

xD


iirc i didnt learn to multiply until grade 4. poor school districts suck
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