[Katy Urbano]

5x + 3y = 3
3x - 2y= 17
:confused:

[Perito]

Multiply the top equation by 2. Multiply the bottom equation by 3. Add the left sides and add the right sides and see what happens.

Alternatively, multiply the top equation by 3. Multiply the bottom equation by -5. Add the left sides and the right together and see what happens.

[Michalla]

2x+2/3y=-8
1/2x-1/3y=1

[Unknown008]

Michalla, you should have started your own thread.

In elimination, you need to get one of the variables have the same coefficient as another similar variable in the other equation.


For example, if you have
x + y = 1
2x + 3y = 1

You either make the first x become 2x by multiplying everything you have by 2, or you make the first y become 3y by multiplying everything in the first equation by 3.

This will give:
2x + 2y = 2
2x + 3y = 1

Now, you can subtract the first from the second like this:

(2x + 3y) - (2x + 2y)= (1) - (2)

This way, you eliminate x, since 2x - 2x gives zero, leaving only y:

2x - 2x + 3y - 2y = 1 - 2
0 + y = -1
y = -1

Now, try the same with your question.
How can you make 1/2 x become 2 x?
Or how can you make 1/3 y become 2/3 y?