Question 789093: Can someone help me solve this?
Solve the system by graphing both equations on the same axes. Give the ordered pair for the point of intersection.
5x+5y=8
x=4-y
Answer by KMST(5328)   (Show Source):
You can put this solution on YOUR website! Note: I can tell that the system  has no solution. The lines are parallel. There is no way to be completely sure that two lines are parallel just from the graph (You need to do some calculations), so either you have a typo or this the wrong problem, and can only confuse students.
To graph one line you need to plot two points and connect them with a straight line.
Using grid paper is recommended.
For  <-->
Substituting  gives us  and we have the point (0,4).
Substituting  gives us  and we have the point (4,0).
For  the same trick would give us points (0,8/5) and (8/5,0), which are too close together to draw the line accurately.
We could substitute and to get
--> --> for point (0,8/5), and
--> --> --> --> for point (4,-12/5)
 If you calculate the vertical distance between one green point and the blue one right above it, you realize that is  at and at .
 and 
That tells you that the lines are parallel.
There is no intersection, and so there is no solution.
If , multiplying both sides times 5 we get 
Since  cannot be equal to 20 and to 8 at the same time, it was obvious from the start that there was no solution.
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