x + y = 6
y = 6 - x
substitute the x values to find the value of y
x ║ -2 ║ -1 ║ 0 ║ 1 ║ 2 ║ 3
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y ║ 8 ║ 7 ║ 6 ║ 5 ║ 4 ║ 3
Graph:
