You can put this solution on YOUR website! graph x+y=-2 and 3x-y=10 using the graphical method
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Arrange the equations into the general (y=) form and plot both graphs
1st eq:
x + y = -2
y = -x - 2
:
2nd eq:
3x - y = 10
-y = 10 - 3x
y = 3x -10; y has to be positive, mult eq by -1
:
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1st eq (purple):
as an example find y when x = -4, substituting for x in; y = x - 2
y = -(-4) - 2
y = +4 - 2
y = 2
Enter 2 for y in the table, do the same for x=0 and x=+4, you should get:
x | y
-------
-4 |+2
0 |-2
+4 |-6
:
2nd eq (green):
do the same in y = 3x - 10
x | y
--------
-1|-13
0|-10
+4|+2
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Plot this as given, the graph should look this:
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The solution is the x/y coordinate where the graphs intersect
You can see this point occurs when x = +2, y = -4
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You can prove this by substituting 2 for x in both equations and see that
y = -4 in both equations
:
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