Question 132883
x+7y=7}}}
{{{x=4-7y
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substitute the value of "x" in the 2nd equation into the 1st to get:
4-7y+7y=7
4 = 7
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This happened because I assumed the x and y in the one equation 
were the same as the x and y in the other.
That assumption lead to the contradiction.
The system of equation is said to be inconsistent.
There is no solution.
If you graph the two equation you will get two parallel lines.
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Cheers,
Stan H.