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Question 153545: Please help me solve the following graphing question (from the worksheet):
Graph:
x+y=5
3x-y=11
On my own, i found that the y-intercept formula for x+y=5 was y=-x+5. I also found out that the y-intercept formula for 3x-y=11 was y=3x-11. Although i'm not completely sure i'm correct, i'm quite not sure on how to graph these two equations.
Answer by Fombitz(32388)   (Show Source):
You can put this solution on YOUR website! You're correct for both.
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Now that you have the y intercept and the slope you can plot the graph.
The y-intercept for the first line is 5 or (0,5).
Plot it.
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You can find another point using the slope of -1.
That means for a positive step in x, you take an equal step in the negative direction in y.
From (0,5) moving 1 in x, -1 in y would give you (1,4).
If you don't want to use slope or it's cumbersome,
another useful point to plot is the x-intercept.
Set y=0 and solve for y.
(5,0) Plot that too.
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Then draw the line that connects those two points.
Line 1 is done.
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y=3x-11
Line 2- y intercept (0,-11)
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The slope is 3, so for every step in x, you take 3 steps in y.
(0,-11)
(1,-8)
(2,-5)
(3,-2)
(4,1)
(5,4)
(6,7)
(7,10)
We have many to choose from.
(7,10)
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Looks like an intersection at x=4
Line 1 : 
(4,1)
Line 2 : 
(4,1)
They share a common intersection point at (4,1).
That is the solution to system of equations.
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