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HarajukuGirl
Jan 24, 2008, 08:37 AM
Question:

If -2x+3=7 and 3x+1=5+y what is the value of Y?
Choices
! 1
2. 0
3. -10
4. 10

answer: 3 (-10)

But my question is how?

I been trying so hard ot fugire out why it equals.. I plugged in numbers, used the eqation solver and I got nothing >.<

Please help! I have my math regents in about an hour so I am trying to get some last minute help.

ISneezeFunny
Jan 24, 2008, 08:41 AM
well. That's a problem... seeing how there's no Y in the equation at all. Rewrite the equation correctly.

HarajukuGirl
Jan 24, 2008, 08:44 AM
Sorry* Fixed it

ISneezeFunny
Jan 24, 2008, 09:00 AM
... look at the equation again.

3x+1=5=y

??

HarajukuGirl
Jan 24, 2008, 09:04 AM
Okay its fixed... agian lol

ISneezeFunny
Jan 24, 2008, 09:08 AM
-2x+3=7

subtract 3 from both sides

-2x = 4

divide by -2 on both

x = -2

use this x to the other equation

3x+1=5+y

3(-2) + 1 = 5 + y

-6 + 1 = 5 + y

-5 = 5 + y

subtract 5 from both sides

-10 = y

take your time doing these problems.

HarajukuGirl
Jan 24, 2008, 09:44 AM
>.<
Thank you.

I have about 3 hours to take a 39 problem test so I should be okay.. Im just so worried I'm not ready, I don't know much material.
Thanks again.