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put this solution on YOUR website!three times one number plus -7 times another number equals 21
:
3x + -7y = 21
:
3x - 7y = 21
:
-7y = -3x + 21
:
Multiply by -1
7y = 3x - 21
:
y =

x -

y =

x - 3
:
Some integer values, ignoring 0;
x=14, y=3
x=21 y=6
x=28 y=9
x=35 y=12
note as x increases by 7, y increase by 3