SOLUTION: If a system of linear equations intersects at every point what does that mean?

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Question 743668: If a system of linear equations intersects at every point what does that mean?
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

If these two or more linear equations intersect, that point of intersection is called the solution to the system of linear equations.
How many solutions can systems of linear equations have?
Case I: 1 solution
This is the most common situation and it involves lines that intersect exactly 1 time.
Case 2: No solutions
This only happens when the lines are parallel. As you can see, parallel lines are not going to ever+meet.
Case 3: Infinite solutions
This is the rarest case and only occurs when you have the same+line.
Consider, for instance, the two lines below
y+=+2x%2B1 and
2y+=+4x+%2B2
These two equations are really the same line.

Example of a system that has infinite solutions:
Line 1: y+=+2x+%2B+1
find x and y-intercept
set x=0 and find y-intercept
y+=+2%2A0+%2B+1 => y+=+1; so, y-intercept is at (0,1)
set y=0 and find x-intercept
0+=+2x+%2B+1 => 2x+=+-1=> x+=+-1%2F2; so, x-intercept is at (-1%2F2,0)

Line 2: 2y+=+4x+%2B+2
set x=0 and find y-intercept
2y+=+4%2A0+%2B+2 => 2y+=2=> y+=1; so, y-intercept is at (0,1)
set y=0 and find x-intercept
2%2A0=+4x+%2B+2 => 0-2+=4x=> x+=+-2%2F4=> x+=+-1%2F2; so, x-intercept is at (-1%2F2,0)

on a graph you will see only one line:

+graph%28+600%2C+600%2C+-10%2C10%2C+-10%2C+10%2C+2x+%2B+1%2C+2x+%2B+1%29+