Please help me System of linear equation in two variables!!!

[Steven G]

Beer soaked reply follows.

Yes it is.

I will disagree with you with on this one as I side with The Cat.
Here is my logic. If I substitute (assume) x = 6 into (assume) y =7, then I come away with y=7. However this is not the solution! Any comments?

 

[Steven G]

Thanks but can I use Elimination and substitution method to solve this???

I updated my previous post to include an answer to your question. Why would you want to use either method when you can just read off the answer?

 

[Steven G]

If y=7 and x=6 then the point of intersection is (6,7). Just read off the answer.

For the record if you have y=7 and y=3x+1, then the point of intersection will be where y=7 (and you still need to find x)

 

[Bea]

I am going to give this one.

Draw any vertical line and you will see that while the y value changes, the x value does not change. So the form of a vertical line is x=c, where c is a constant.

Draw any horizontal line and you will see that while the x value changes, the y value does not change. So the form of a horizontal line is y=k, where k is a constant.

So if you have a system of equations where for example
x=7
y=9
then the solution is simple (7,9).

There is no need to substitute or eliminate.
You can't eliminate since there is no y to eliminate in the vertical line and x to eliminate in the horizontal line.
There is nothing to substitute from one equation into the other equation.

Thank you very much it is very helpful