7x - 3y = 4
2x - 4y = 1

Which of the following systems is not the same as solving the system shown?

28x - 12y = 16 and -6x + 12y = -3
14x - 6y = 4 and -14x + 28y = 1
-28x + 12y = -16 and 28x - 56y = 14

.. am I supposed to be multiplying them?

Question

7x - 3y = 4
2x - 4y = 1

Which of the following systems is not the same as solving the system shown?

28x - 12y = 16 and -6x + 12y = -3
14x - 6y = 4 and -14x + 28y = 1
-28x + 12y = -16 and 28x - 56y = 14


.. am I supposed to be multiplying them?

reneeshumpert · Answer

the equations

texaschic101 · Answer

look at your first equation...7x - 3y = 4
now what would you have to multiply 7x by to get 28x.....you would have to multiply by 4.
so 4 * (7x - 3y = 4) = 28x - 12y = 16

now check out your second equation..2x - 4y = 1
now what would you have to multiply 2x by to get -6x....that would be -3
so -3 (2x - 4y = 1) = -6x + 12y = -3

so I would say the first one works.....do you see what I did ? Do you understand ?
If they didn't match, I would have gone to the other answer choices

reneeshumpert · Answer

No I'm not really understand , explain a little more? And future reference I like to walk through the problem lol not just get the answer.

reneeshumpert · Answer

like where did the 4 come in at ? or that was an educated guess?

texaschic101 · Answer

now if I wanted to try the second answer choice....7x - 3y = 4
what would you have to multiply 7x by to get 14x....you would have to multiply by 2
2(7x - 3y = 4) = 14x - 6y = 8.....that does not match...not the answer

reneeshumpert · Answer

Oh so basically you're using the answer choices to fill in for the equation ?

texaschic101 · Answer

I am basically multiplying the original equations by a certain number to see if it matches the answer choices....does that make sense ??

reneeshumpert · Answer

Oooo yeah that makes sense, I get it now

reneeshumpert · Answer

but how did you come up with those numbers?

texaschic101 · Answer

ok...your original equation....7x - 3y = 4
I was just trying the first answer choice...28x + 12y = 16...
the number I want to multiply by was found by 7x * what = 28x.....so the number I want to multiply the entire equation by is 4
4(7x - 3y = 4)
28x - 12y = 16
Is this making any sense ?

reneeshumpert · Answer

your answer was actually incorrect. thank you tho

texaschic101 · Answer

oh..I am so sorry....your right...
7x - 3y = 4...multiply by -4
-4(7x - 3y = 4) = -28x + 12y = -16
so sorry...answer is the third one