SOLUTION: solve the system by addition or substitution 20x - 5y = -12 y = 4x +3 Thank you.

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Question 90658: solve the system by addition or substitution 20x - 5y = -12
y = 4x +3
Thank you.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve the system by addition or substitution 20x - 5y = -12
y = 4x +3
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Substitute y=4x+3 into the 1st equation to get:
20x - 5(4x+3) = -12
20x -20x -15 = -12
-15 = -12
This is a contradiction.
There is no solution for the system of equations.
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If you graph the two equations you will notice the lines are parallel:
Solving the 1st equation for y you get:
y = 4x+(12/5)
Graphing both equations you get:
graph%28400%2C300%2C-10%2C10%2C-10%2C10%2C4x%2B%2812%2F5%29%2C4x%2B3%29
Cheers,
Stan H.