SOLUTION: How do I slove x+Y=-1 and 2x-y=-8 The problem says Find the Solution to the system by graphing

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Question 65153: How do I slove x+Y=-1 and 2x-y=-8
The problem says Find the Solution to the system by graphing
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
How do I solve x+y=-1 and 2x-y=-8
The problem says Find the Solution to the system by graphing
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Put both equations in slope-intercept form:
y=-(x)-1
This has a y-intercept of (0,-1) and a slope of -1
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y=2x+8
This has a y-intercept of (0,8) and a slope of 2
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graph%28600%2C400%2C-10%2C10%2C-10%2C10%2C-x-1%2C2x%2B8%29
Where do these line intersect?
Where they intersect the y-values are equal.
So, write -x-1=2x+8
3x=-9
x=-3
Substitute to find y, as follows:
y=2x+8
y=2(-3)+8
y=2
The point of intersection is (-3,2)
Cheers
Stan H.