Question 71267
x+y=4
y=-x+4
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2x-y=-4
-y=-2x-4
y=2x+4
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{{{ graph( 300, 200, -6, 5, -10, 10, y = -x +4, y = 2x +4) }}} (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions y = -x +4 and y = 2x +4).