Question 700029: solve by graphing y=x + 1
y= -2x -2
Answer by KMST(5328)   (Show Source):
You can put this solution on YOUR website! Each of the two linear equations graphs as a straight line.
You only need two (well chosen) points to graph a line.
A well chosen point is one that is easy to calculate and makes the graph look good.
Usually,  is a good choice, and will give you one point.
(If one choice does not work well, try again).
You would want to calculate your points for both lines before you start graphing,
so as to know what part of your x-axis and y-axis the graph must show.
However,for clearer explanation,
I will show steps to calculate and graph one line first,
and then I will show how to calculate and add the other line.
For 
-->  gives you point (0,1).
 -->  gives you point (-5,-4).
To graph , plot those two points and connecting them with a straight line.
 show the points (circled) and the line.
For 
-->  gives you point (0,-2).
-->  gives you point (0,1).
To graph , plot those two points and connecting them with a straight line.
Adding the second line, 
it looks like the lines intersect at the point (-1,0), with  and  .
We need to substitute those values and verify that the solution is exactly that.
For and ,  , the solution checks.
For and ,  , the solution checks.
So  with  is the solution.
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