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Adderb
Jan 21, 2007, 12:39 AM
y = -x/2
2x - 3y = -7

I have reached this point:

2x - 3(-x/2) = -7

Can someone help me? Thanks!

Capuchin
Jan 21, 2007, 01:30 AM
Okay, the next step is to expand the brackets:

2x + 3x/2 = -7

then collect similar terms

7x/2 = -7 ---> 7x = -14

x = -2

you can use this value for x to work out y, using one of your initial equations.

Then you can use the other equation to check if your values are correct.

Hope this helps

Adderb
Jan 22, 2007, 01:31 AM
y = -x/2
2x - 3y = -7

I have reached this point:

2x - 3(-x/2) = -7

Can someone help me? Thanks!!
Still confused, how did you get 7x/2 = -7

Capuchin
Jan 22, 2007, 01:33 AM
In order to add fractions, you need to give them the same denominator.
so we convert 2x into a fraction with denominator 2

2x = 4x/2

putting this into your equation:

4x/2 + 3x/2 = -7

Now you can add the numerators:

7x/2 = -7

Apologies for not elaborating on this before, I did it in my head :p